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Organic
Chemistry
A report based on the topic of Organic Synthesis
and our learning experience for WOW! 08 Attachment at:
Nanyang Technological University, School of Physical and Mathematical Sciences
Division of Chemistry and Biological Chemistry
1
Report written by: Loo Sze Ying Serene, CG 01/08
Organization attached to: NTU SPMS, Division of Chemistry and Biological Sciences
Teacher Mentor (TJC): Mr Terence Ong
External Mentor (NTU): Professor Loh Teck Peng
Groupmates: Sadia Riaz, G. Girish, Lin Wan Shi, Sim Wen Jun Eran
But I do respect chemists for their noble spirit of creation and making good for society.
Content Page:
A. Introduction
A.1 What is Organic Chemistry?
A.2 Importance of Organic Chemistry
A.3 NTU, SPMS (Division of Chemistry and Biological Chemistry)
B. Our Learning Process
B.1 Brief Overview of Our Attachment
B.2 Our Attachment Work Schedule at NTU, SPMS
• Week 1: Background Reading on Organic Chemistry in TJC
• Week 2: Practice on Use of Software (i.e. ChemDraw and SciFinder)
• Week 2 & 3: Application of SciFinder to Final Project - Chiral Synthesis
• Week 4: Preparation of Prof. Loh’s Lecture and Chemical Lists
C. Final Project on Chiral Synthesis
C.1 What is Chiral Synthesis?
C.2Relation of Chiral Synthesis to our project
D. Other Lessons Learnt
D.1 Organic Chemistry Laboratory Technique: Extraction
D.2 Organic Chemistry Laboratory Technique: Column Chromatography
D.3 Organic Chemistry Laboratory Equipment – Rotatory Separator
E. Difficulties Faced and Solutions to Them
E.1 Deciphering Technical Terms
E.2 Working on Wrong Compound for Final Project
F. Conclusion
2
It’s not only about Chemistry, but the spirit of trying.
Afterall, Chemistry is Chem-Is-Try!
A. Introduction
A.1 What is Organic Chemistry?
“Organic chemistry is a specific discipline within chemistry which involves the scientific
study of the structure, properties, composition, reactions and preparation of chemical
compounds consisting primarily of carbon and hydrogen, which may contain any number
of other elements, including nitrogen, oxygen, halogens as well as phosphorus, silicon
and sulfur.”
Definition of Organic Chemistry
Source: Wikipedia
To put it simply, Organic Chemistry is the study of carbon compounds, their properties,
chemical structures and reactions. As elements present in organic compounds are mostly
limited to non-metals such as C, H, O, N, S, R, Cl, Br and I, most organic compounds are
non-polar. In order for a compound to be classified as organic, the carbon atom(s) in the
compound must undergo hybridization (sp, sp2
or sp3
). This is because hybridization of
carbon atoms enables the formation of single, double or triple bonds, thus extending the
structure of the compound and determining its displayed formula.
Three types of hybridization a carbon atom can undergo:
Example of a displayed formula:
Displayed formula of ethanoic acid
3
sp3
hybridization
sp2
hybridization sp hybridization
A.2 Importance of Organic Chemistry
Due to its great influence on technology, Organic Chemistry plays a vital role in our
lives. Organic Chemistry is fundamental to Biology (biological molecules such as DNA
are in fact organic compounds) and the drug industry (new organic increases chances of
creating new drugs). It is especially important in the pharmaceutical field as different
enantiomers have different biological activity. It is due to this difference in biological
activity that often results in side effects of drugs.
Organic compounds derived naturally are major sources of new drugs and enzymes (e.g.
aspirin originating from willow tree bark). The modification of existing organic
compounds in laboratories can result in creation of new drugs too. By changing the types
of bonds or side chains, properties and characteristics of compounds are often modified
too. This results in the derivation of new organic compounds with properties different
from their ‘parent’ compounds.
A.3 NTU, SPMS (Division of Chemistry and Biological Chemistry)
Central theme of research: Organic Synthesis
External mentor: Professor Loh Teck Peng
NTU, SPMS (Division of Chemistry and
Biological Chemistry) specializes in
Organic Chemistry research, especially
focusing on Organic Synthesis. One
objective in this field of study is to discover
new reactions and hypotheses via the
synthesis of products derived naturally.
Another objective is to discover new
reactions and hypotheses via the synthesis of
products derived naturally.
Four main focuses of research activities:
♥ Green Chemistry
- Exploring new reactions with water or ionic liquids as solvent/ solvent-free
reactions
♥ Enantioselective Reactions
- Development of water-based asymmetric reactions with high catalytic
turnover and new chiral metal complexes as end-products
♥ Development of New Synthetic Methodology
- Breakthrough in concepts, mechanistic perception and synthetic approach
♥ Synthesis of Natural Products
4
New building of NTU, SPMS
- Synthesis of numerous organic compounds derived naturally
B. Our Learning Process
B.1 Brief Overview of Our Attachment
WOW! 08 is a programme specially organized for TA3 students to work in small groups
with a teacher mentor and an external partner for a comprehensive project. They report to
their respective external partners for attachment four times a week and return to school
every Friday for bridging lessons and conferencing with their teacher mentors. ‘Wonder,
Observe, Weave’ – these three objectives of WOW! 08 symbolizes that students should
explore an area of interest in their attachments, observe to learn, and consolidate
knowledge and skills acquired by the end of the attachment period.
For our attachment in NTU (SPMS), our
main task is to conduct Organic Chemistry
research related to organic synthesis and
structure determination using analytical
methods such as elemental analysis. It is
mostly done with the aid of programmes
such as ChemDraw and SciFinder, and
websites like Sigma-Aldrich (further
details will be provided in Section B).
Other than conducting research, the
researchers also craft projects for us where
the data collected may then be used for
their lectures or research papers.
B.2 Our Attachment Work Schedule at NTU, SPMS
• Week 1: Background Reading on Organic Chemistry in TJC
For Week 1 of our attachment, NTU was not ready to conduct our attachment as their
new SPMS building was not yet ready. As a result, my teammates and I were expected to
report to college everyday to do research and read up on topics related to Organic
Chemistry (mentioned in description of our attachment in WOW! 08 handout when we
chose our attachment choices). Also, we did revision on what we learnt regarding
Organic Chemistry in Year 2: Hybridization. (For information on hybridization, please
refer to Section A.1 of this report)
The following are topics we researched on during Week 1:
- What is Organic Chemistry?
- Importance of Chemistry in our lives
- Alkanes and Aromatic Hydrocarbons (Benzene and Alkylbenzene)
- Mechanism of reactions involving different types of organic compounds
5
Girish constructing diagrams of organic
compounds for Prof. Loh’s lecture
- Research projects under Prof. Loh’s charge
- Green Chemistry: The Twelve Principles of Green Chemistry
Two group meetings were also held to ensure clear understanding of our attachment and
the central theme of research at NTU. My teammates and I regarded group meeting to be
proper platforms for discussion and gathering of useful information for our attachment.
For the first meeting, each member was also assigned a specific topic for further research
and reading from the list of research projects under Prof. Loh’s charge. During the second
meeting, each member presented his/ her findings on the topics they were assigned to
previously. Also, we even branched out to work on difficulties met and solutions to them.
Our first Conferencing Friday was held on 11 January 2008. We had a small meeting
with our teacher mentor, Mr Terence Ong to discuss our progress at attachment and his
work expectations of us. Also, we were given instructions regarding our attachment at
NTU on next Monday. There was also clarification of problems faced and their solutions.
• Week 2: Practice on Use of Software (i.e.
ChemDraw and SciFinder)
Our attachment at NTU officially began on
Monday, 14 January 2008. Firstly, we were given
a brief tour around the new SPMS building by
Prof. Loh. The new SPMS building contained
specially designed laboratories, study rooms with
state-of-the-art facilities and other rooms
specifically used for equipment storage. Each
storey of the new SPMS building is meant for a
specific area of research. For instance, all
laboratories conducting Biological Chemistry
related research are located on the first storey.
6
Cycloalkanes, a type of alkanes
Benzene, an Aromatic Hydrocarbon
Organic Chemistry Research Laboratory
The picture on the left is one of the Organic Chemistry research laboratories which were
not yet in use by the researchers then.
7
For Week 2 and 3, my team and I worked in another faculty, NTU School of Material
Sciences and Engineering for attachment. For the first half of Week 2, we mainly focused
on learning two programs, widely used by researchers and students at NTU, ChemDraw
and SciFinder. As the details of our final project were given to us on Wednesday, we
spent the next two days of Week 2 using SciFinder to work on our final project.
ChemDraw
ChemDraw is a major chemical drawing
program that enables stereochemistry
recognition and display, multi-page
documents and professional structure
drawing. It is the software NTU
professors use to construct diagrams of
chemical reactions and structures of
molecules in preparation for their
lectures. ChemDraw enables perfect
structure drawing of molecules and
prevents untidiness. The diagrams drawn
can be duplicated for further use in the
future by saving the picture file.
After mastering the basics, we also moved on to draw molecules with more complicated
structures and chemical reactions involving these complicated molecules.
8
Complex molecular structure under construction
9
Chemical reaction involving molecules with complex structures
SciFinder
SciFinder is a program used by universities and other academic institutions to increase
convenience for multi-database searching. SciFinder enables users to gain access to
references of a research topic from well-known databases all over the world, such as
American Chemical Society and Wiley InterScience. We can further sort the search
results by adding criteria (e.g. publication year and author name). Even if we need to gain
urgent access to publications by a certain author or database, we can do so easily. This
greatly improves convenience and saves time.
One notable point is that SciFinder is
also designed with a graphic
interface; hence enabling structure
drawings done by the user to be used
as a reaction query for explore
single- or multi-step reactions
involving that substance-of-interest.
Moreover, we can also gain access to
further details regarding the
substance-of-interest (which can take
the form of a reagent, reactant,
product, solvent or catalyst). The
picture of the left shows the
substance-of-interest as a reactant
about to be used as search query to
search reactions it was involved in.
10
Substance-of-Interest drawn as a reaction query
Search results arranged according to a specific publication year
Moreover, SciFinder can be used to
identify a certain substance-of-interest
and at the same time, provide further
details on it. By entering any chemical
name of the substance or its CAS
Registry Number, we will be able to
gain access to its CAS Registry record.
The CAS Registry record of a
substance is a record which contains
property data of that substance. An
example of a CAS Registry record
found in SciFinder can be seen in the
picture below.
(Note: CAS registry numbers are unique numerical identifiers for chemical compounds,
polymers, biological sequences, mixtures and alloys.)
11
CAS Registry record (property data) of a substance-of-interest
For SciFinder, the researchers would usually select lists of online references from their
handouts on Organic Chemistry for us to search for the PDF documents of those
references. We would then label those documents before saving them in a folder on
Desktop. Sometimes the online references given to us contained data on chemical
reactions they were interested in exploring on then, locating and saving the data in the
computer would save them the trouble of searching for those resources again.
We also had our second Conferencing Friday. We mainly gave feedback onour
attachment, what we have learnt so far and what we hoped to see improvement in. We
also sought help from our teacher mentor Mr Ong on the project given to us by our
researchers in NTU. Our attachment ran smoothly, hence it was a rather brief meeting.
• Week 2 & 3: Application of SciFinder to Final Project - Chiral Synthesis
After learning how to use ChemDraw and SciFinder, we were assigned our final project
to work on for the rest of Week 2 and 3. However, we encountered some difficulties (to
be elaborated in Section D) which greatly shortened the amount of time available to work
on our project.
Basically, we were given the chemical structure of a certain substance (Compound B)
which we were supposed to identify and look up chemical reactions involving it. In the
process of researching chemical reactions involving Organic Compound B, we should
also identify possible ‘Reactant A’s and ‘Product C’s. However, it is important to note
that Reactant A must contain at least one double bond but not any aromatic rings.
Suggested plan to carry out research:
1) Identify full structure of Organic Compound B. From there, obtain its full
chemical formula to retrieve information on its properties and chemical reactions
involving it.
2) Properties of Organic Compound B can be obtained from the Internet. Chemical
reactions involving Organic Compound B can be retrieved from SciFinder.
12
Product C+Reactant
A
Organic Compound B
Tasks: Make use of the given chemical structure to identify Organic Compound B
Identify possible ‘Reactant A’s and ‘Product C’s
Identify underlying mechanism of these chemical reactions
We discovered that Organic Compound B contains four functional groups known as
methyl groups. Each methyl group has a chemical formula of CH3, thus we came to the
conclusion that Organic Compound B has a chemical formula of C12H24B2O4.
After obtaining the chemical
formula of Organic Compound
B, we proceeded to research on
chemical reactions involving it
using SciFinder. To do this, we
used the graphic interface in
SciFinder to find chemical
reactions involving Organic
Compound B.
We drew the structure of
Organic Compound B and a
double bond (having labelled
them as ‘Reactant/ Reagent’).
Below are some criteria we
included to filter our search
results.
Search results should contain:
• Product to be of a substructure of a more complex structure
• Only single-step catalyzed reactions
• Research papers published in the year 2007
We found 16 search results which fit the criteria in total. As we were clueless about the
underlying mechanism of the chemical reactions, we sought help from our supervisor and
discovered that the underlying mechanism was Chiral Synthesis. We proceeded to do
some research on the topic of Chiral Synthesis.
(Note: The topic of Chiral Synthesis will be discussed in Section C)
Finally we compiled all the information we obtained into a PowerPoint presentation and
handed it in for file check by Mr Ong on our third Conferencing Friday.
(PowerPoint Presentation can be found in WOW! 08 File ‘Attachment Work’ folder)
13
Hand drawn chemical structure (search query in SciFinder)
Me
Me
Me
Me
Me
Me
Me
Me
B
O
O
B
O
O
(Step 1.2)
+
CH CH3C CH2
(Step 1.2)
1.2 S:PhMe, 14 h, rt
1.1 C:213843-90-4, C:Ph2-pentadienone Pd, S:PhMe,
1 h, rt
Me
Me
Me
Me
Me
Me
Me
Me
Me
B
CH2
B
O
O
O
O
R
68%
NOTE: stereoselective,
Reactants: 2, Catalysts: 2, Solvents: 1,
Steps: 1, Stages: 2
Catalyst
Reactant A
Catalyst
Meanwhile, below are some examples of search results we obtained:
• Reaction 96
• Reaction 123
14
Me
Me
Me
Me
Me
Me
Me
Me
B
O
O
B
O
O
(Step 1.2)
+
Ph CH C CH2
(Step 1.2)
1.2 24 h, rt
1.1 C:913706-72-6, C:Ph2-pentadienone Pd, S:PhMe,
1 h, rt
Me
Me
Me
Me
Me
Me
Me
Me
Ph
B
CH2
B
O
O
O
O
S
53%
NOTE: stereoselective, optimized on catalyst,
Reactants: 2, Catalysts: 2, Solvents: 1,
Steps: 1, Stages: 2
Reactant A
Organic Compound B
Product C (% symbolizes
effectiveness of catalyst)
Other information about this reaction
Organic Compound B
Product C (% symbolizes
effectiveness of catalyst)
Other information about this reaction
• Week 4: Preparation of Prof. Loh’s Lecture and Chemical Lists
Preparation of Prof. Loh’s lectures:
For Week 4, the new SPMS building was finally ready for use. Thus our attachment was
no longer conducted at NTU School of Material Sciences and Engineering, but at the new
School of Physical and Mathematical Sciences. Having mastered using ChemDraw and
SciFinder, as well as finished our final project, we could help with actual work in NTU.
Using ChemDraw, we constructed diagrams of chemical reactions and molecules in
preparation of Prof. Loh’s lecture on ‘Catalysis and Green Chemistry’. Generally, his
paper covered on several topics like the two main groups of catalysts (homogenous
catalysts and heterogeneous catalysts), importance of catalysts in the manufacturing
industry, and the implementation of Green Chemistry to reduce waste as a by-product by
the end of a chemical reaction. Thus, the diagrams we constructed mostly depicted
catalyzed biological reactions.
15
A Catalyzed Adsorption Process
16
Preparation of Chemical Lists:
As mentioned in Section B.2, SciFinder can be used to identify a substance-of-interest
through its name or CAS Registry number and provide further details on it. By entering
the chemical name of any substance or its CAS Registry Number, we could gain access to
its CAS Registry record. However, we discovered that a website ‘Sigma Aldrich’ is also
capable of doing so. Sigma Aldrich has similar functions as SciFinder, except that
chemists could even order chemicals in specific amounts they needed online. This is
comparatively more convenient than SciFinder.
Screenshot of Sigma-Aldrich and its functions
Below is an extract from one of the chemical lists we prepared:
Name CAS Original
pathalic anhydride [85-44-9] 1kg
Triethyl orthoformate [122-51-0] 1.01 * 3
methyl acrylate ee90 [96-33-3] 1.01
Vinyl acetate [108-05-4] 1.01 * 2
Methyl bromoacetate [96-32-2] 500ml
Trimethylactic anhydride ee90 [1538-75-6] 100g
Maleic anhydride [108-31-6] 1kg
sodium α-ethylhexanoate [19766-89-3] 1l
4-Methylcinnamic acid [1866-39-3] 20g
Methyl 2-bromopropionate [5445-17-0] 5.0mL
α-bromobutyric acid p890 [80-58-0] 80ml
We also had our very last Conferencing Friday for our attachment. Generally, there was
discussion on deadlines for our WOW! 08 files and we were free to ask any questions we
had regarding the contents of our reports and WOW! 08 files.
17
An illustration of chirality in D-Alanine and L-Alanine
C. Final Project on Chiral Synthesis
C.1 What is Chiral Synthesis?
Chiral Synthesis is in essence organic synthesis that introduces one or more new desired
elements of Chirality. Chiral synthesis is very important in the pharmaceutical field,
especially when it comes to manufacturing of drugs. Different enantiomers have different
biological activity; this is why side effects of drugs arise. Due to the problem of side
effects, an external factor has to be introduced such that chiral synthesis occurs, thus
forming a chiral product which counters the side effects.
Chirality is an asymmetric property that
refers to the inability of an object to
superimpose on its mirror image.
Enantiomers are stereoisomers which are
non-superimposable on each other, just
like human hands. The right hand is non-
superimposable on the left hand; no matter
how the two hands are placed together, not
all major features of both hands coincide.
They have their ‘handedness’, which is
similar to chirality in molecules.
18
Chirality of our human hands
C.2 Relation of Chiral Synthesis to our project
Chiral synthesis is important in the chemical reaction which we were supposed to
research on as it helps to break the B-B bond of Organic Compound B, thus enabling the
boron to attack another reactant and form a new product. Initially the reactant was
achiral, but after the introduction of a chiral catalyst, the product formed was chiral.
For the diagram below, we can see that Organic Compound B was a chiral molecule
whereas Reactant A was an achiral molecule initially. By introducing an external factor
(i.e. a chiral catalyst) into the chemical reaction, organic synthesis occurs. As a result,
Product C formed is a chiral molecule.
A double bond is broken from Reactant A (H3C – CH = C = CH2) and the B - B bond in
Bis (pinacolato) Diboron molecule. In the presence of catalysts, the double bond between
C and CH attacks the B-B bond, forming a new single bond between boron and carbon,
as well as a double bond between CH2 and C.
19
Me
Me
Me
Me
Me
Me
Me
Me
B
O
O
B
O
O
(Step 1.2)
+
CH CH3C CH2
(Step 1.2)
1.2 S:PhMe, 14 h, rt
1.1 C:213843-90-4, C:Ph2-pentadienone Pd, S:PhMe,
1 h, rt
Me
Me
Me
Me
Me
Me
Me
Me
Me
B
CH2
B
O
O
O
O
R
68%
NOTE: stereoselective,
Reactants: 2, Catalysts: 2, Solvents: 1,
Steps: 1, Stages: 2
Organic Compound B
Reactant A
Catalyst
Product C (% symbolizes
effectiveness of catalyst)
Other information about this reaction
Chiral synthesis of organic compounds in Reaction 123
D. Other Lessons Learnt
D.1 Organic Chemistry Laboratory Technique: Extraction
In organic chemistry labs, liquid-liquid extractions are
always performed using a separatory funnel. During
extraction, two immiscible liquids (forming separate
layers when mixed) will be mixed inside the separatory
funnel and left to settle. Eventually two layers will be
formed again at the end of the mixing process. One is
the aqueous layer while the other is the organic layer.
The aqueous layer and organic layer are to be contained
in different beakers. The layer with the higher density
flows through the stopcock down the separatory funnel
into the beaker while the layer with lower density has to
be poured from the top of the separatory funnel into
another beaker to prevent contamination.
Self-Notes:
√ Sometimes during mixing, an emulsion may be observed as the boundary between
the aqueous and organic layers might be unclear. We can add another external
agent to increase polarity to one of the layers, so as to increase the difference in
polarity between the two layers. This ensures that the two layers are more likely
to be immiscible, thus lowering chances of observing an emulsion.
√ DO NOT label the beakers containing the two layers as ‘bottom layer’ and ‘top
layer’. This is because the top and bottom layers might change over time. Be
specific; label them as aqueous layer and organic layer.
√ DO NOT transfer the layer
with lower density into a
beaker by letting it flow
down the separatory funnel
as this may result in serious
contamination.
20
A separatory funnel
Supervisors carrying out extraction process
D.2 Organic Chemistry Laboratory Technique: Column Chromatography
21
Silica Gel
Organic Compound
Column chromatography in process
Column chromatography is one of the
most commonly conducted experiments
at NTU. Its one of the most important
experiments to chemists doing Organic
Chemistry research.
Column chromatography is used to
purify chemical compounds from a
mixture of compounds.
In column chromatography, a layer of sand
is topped to protect the organic compound
from the velocity of newly added eluent.
Eluent is apure solvent or a mixture of
solvents added into the column to flow
down it.
As eluent enters the column and flows
through the silica gel, it flows down much
faster than the organic compound. The
purpose of silica gel is to act like a filter to
prevent unwanted chemicals from entering
and flowing down the column as this
changes the rate of reaction. As different
chemicals react differently to silica gel, the
rate at which they flow down the column is
enough to determine the type of
compounds they are.
Different sizes of columns used to
contain different amounts of compounds
D.3 Organic Chemistry Laboratory Equipment – Rotatory Separator
Function: The rotatory separator helps to separate impure solutions into solute (desired
product) and solvent which is poured away into large containers to be
disposed of at the end of the process.
How to use the Rotatory Separator:
1) Inside the container, a water bath is set at the boiling point of the impure solution.
2) When the round-bottomed flask containing the impure solution is added to the
water bath, the flask spins and heat is transferred to all parts of it evenly.
3) The spinning of the round-bottomed flask prevents heat from being applied to a
concentrated point which might result in spillage of the impure solution.
4) Spinning increases the rate of reaction within the round-bottomed flask.
5) As the impure solution is heated to its boiling point, it evaporates, rises upwards as
hot air, gets into contact with the condenser and the solvent condenses. The solvent
flows down the condenser and is collected into another round bottomed flask.
6) At the end of the experiment, the solute will be
used for other experiments while the solvent will
be considered as a toxic waste product to be
thrown away.
22
Waste solvent after experiment
E. Difficulties Faced and Solutions to Them
E.1 Deciphering Technical Terms
While carrying out our research on Organic Chemistry, we encountered many technical
terms which we could not comprehend. Some of these technical terms include chirality,
enantiomers and enantioselective reactions. What I did was to record down these
technical terms just in case we encounter them during attachment.
In the meanwhile, I carried out some research on these technical terms to seek a simpler
explanation of these technical terms. However, I realized that at times the search results
obtained were mostly research papers containing complicated information related to these
technical terms.
Also, I encountered some of the technical terms mentioned above such as chirality and
enantiomers while conducting research for the final project on Chiral Synthesis. With the
help of my other groupmates and supervisors at NTU, I managed to have a clearer idea of
what those technical terms stand for. Also, I managed to apply the new concepts I have
learnt to use when I attempted to explain the underlying mechanism of chemical
reactions.
E.2 Working on Wrong Compound for Final Project
In the course of carrying out research for our final project on Chiral Synthesis, we
received the wrong information and thus worked on the wrong compound for our final
project. Instead of Bis (pinacolato) Diboron (Chemical formula: C12H24B2O4) which we
were supposed to work on, we worked on another compound Carapine Alkaloid
(Chemical formula: C10H28O4).
As a result, we were left with four days to work on our final project (instead of the
second half of Week 2 and the whole of Week 3). Having lost one third of the time to
working on something irrelevant, my groupmates and I had no choice but to push
ourselves harder. We had to approach our supervisor for the full name of Organic
Compound B instead of finding it out ourselves. However our supervisor was very
23
Product C+Reactant
A
Organic Compound B
understanding and in fact guided us by dropping some more clues for our project. Thus,
we were able to finish our project on time for submission.
24
F. Conclusion
On the whole, I believed I have benefitted very much from this attachment, both
intellectually and psychologically. In terms of knowledge, I have gained much valuable
knowledge on Organic Chemistry, especially in the area of Chiral Synthesis. Also, I have
had a clearer idea of how research is carried out in Organic Chemistry laboratories at
NTU and better understanding of Organic Chemistry laboratory techniques.
In terms of psychological benefits, I have had the opportunity to work with researchers
from one of the most well-known universities in the region before my peers. Also, I have
experienced a very different learning style from what I have experienced in Temasek
Academy. Moreover, I have gained greater insight on working with others in a group as
well as others from different nationalities.
Many thanks to:
At NTU
Professor Loh Teck Peng, Dr. Lu Jun, Mr Wang Peng, Mr Xu Yunhe and other
researchers at NTU
At TJC
Mr Simon Foo, Mr Terence Ong and not forgetting, my groupmates consisting of
Wanshi, Eran, Sadia and Girish
Thank you very much for your kind guidance and participation in what has been a very
enriching and memorable attachment for me.
Thank you very much!
25

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Report on Chiral Synthesis

  • 1. Organic Chemistry A report based on the topic of Organic Synthesis and our learning experience for WOW! 08 Attachment at: Nanyang Technological University, School of Physical and Mathematical Sciences Division of Chemistry and Biological Chemistry 1 Report written by: Loo Sze Ying Serene, CG 01/08 Organization attached to: NTU SPMS, Division of Chemistry and Biological Sciences Teacher Mentor (TJC): Mr Terence Ong External Mentor (NTU): Professor Loh Teck Peng Groupmates: Sadia Riaz, G. Girish, Lin Wan Shi, Sim Wen Jun Eran But I do respect chemists for their noble spirit of creation and making good for society.
  • 2. Content Page: A. Introduction A.1 What is Organic Chemistry? A.2 Importance of Organic Chemistry A.3 NTU, SPMS (Division of Chemistry and Biological Chemistry) B. Our Learning Process B.1 Brief Overview of Our Attachment B.2 Our Attachment Work Schedule at NTU, SPMS • Week 1: Background Reading on Organic Chemistry in TJC • Week 2: Practice on Use of Software (i.e. ChemDraw and SciFinder) • Week 2 & 3: Application of SciFinder to Final Project - Chiral Synthesis • Week 4: Preparation of Prof. Loh’s Lecture and Chemical Lists C. Final Project on Chiral Synthesis C.1 What is Chiral Synthesis? C.2Relation of Chiral Synthesis to our project D. Other Lessons Learnt D.1 Organic Chemistry Laboratory Technique: Extraction D.2 Organic Chemistry Laboratory Technique: Column Chromatography D.3 Organic Chemistry Laboratory Equipment – Rotatory Separator E. Difficulties Faced and Solutions to Them E.1 Deciphering Technical Terms E.2 Working on Wrong Compound for Final Project F. Conclusion 2 It’s not only about Chemistry, but the spirit of trying. Afterall, Chemistry is Chem-Is-Try!
  • 3. A. Introduction A.1 What is Organic Chemistry? “Organic chemistry is a specific discipline within chemistry which involves the scientific study of the structure, properties, composition, reactions and preparation of chemical compounds consisting primarily of carbon and hydrogen, which may contain any number of other elements, including nitrogen, oxygen, halogens as well as phosphorus, silicon and sulfur.” Definition of Organic Chemistry Source: Wikipedia To put it simply, Organic Chemistry is the study of carbon compounds, their properties, chemical structures and reactions. As elements present in organic compounds are mostly limited to non-metals such as C, H, O, N, S, R, Cl, Br and I, most organic compounds are non-polar. In order for a compound to be classified as organic, the carbon atom(s) in the compound must undergo hybridization (sp, sp2 or sp3 ). This is because hybridization of carbon atoms enables the formation of single, double or triple bonds, thus extending the structure of the compound and determining its displayed formula. Three types of hybridization a carbon atom can undergo: Example of a displayed formula: Displayed formula of ethanoic acid 3 sp3 hybridization sp2 hybridization sp hybridization
  • 4. A.2 Importance of Organic Chemistry Due to its great influence on technology, Organic Chemistry plays a vital role in our lives. Organic Chemistry is fundamental to Biology (biological molecules such as DNA are in fact organic compounds) and the drug industry (new organic increases chances of creating new drugs). It is especially important in the pharmaceutical field as different enantiomers have different biological activity. It is due to this difference in biological activity that often results in side effects of drugs. Organic compounds derived naturally are major sources of new drugs and enzymes (e.g. aspirin originating from willow tree bark). The modification of existing organic compounds in laboratories can result in creation of new drugs too. By changing the types of bonds or side chains, properties and characteristics of compounds are often modified too. This results in the derivation of new organic compounds with properties different from their ‘parent’ compounds. A.3 NTU, SPMS (Division of Chemistry and Biological Chemistry) Central theme of research: Organic Synthesis External mentor: Professor Loh Teck Peng NTU, SPMS (Division of Chemistry and Biological Chemistry) specializes in Organic Chemistry research, especially focusing on Organic Synthesis. One objective in this field of study is to discover new reactions and hypotheses via the synthesis of products derived naturally. Another objective is to discover new reactions and hypotheses via the synthesis of products derived naturally. Four main focuses of research activities: ♥ Green Chemistry - Exploring new reactions with water or ionic liquids as solvent/ solvent-free reactions ♥ Enantioselective Reactions - Development of water-based asymmetric reactions with high catalytic turnover and new chiral metal complexes as end-products ♥ Development of New Synthetic Methodology - Breakthrough in concepts, mechanistic perception and synthetic approach ♥ Synthesis of Natural Products 4 New building of NTU, SPMS
  • 5. - Synthesis of numerous organic compounds derived naturally B. Our Learning Process B.1 Brief Overview of Our Attachment WOW! 08 is a programme specially organized for TA3 students to work in small groups with a teacher mentor and an external partner for a comprehensive project. They report to their respective external partners for attachment four times a week and return to school every Friday for bridging lessons and conferencing with their teacher mentors. ‘Wonder, Observe, Weave’ – these three objectives of WOW! 08 symbolizes that students should explore an area of interest in their attachments, observe to learn, and consolidate knowledge and skills acquired by the end of the attachment period. For our attachment in NTU (SPMS), our main task is to conduct Organic Chemistry research related to organic synthesis and structure determination using analytical methods such as elemental analysis. It is mostly done with the aid of programmes such as ChemDraw and SciFinder, and websites like Sigma-Aldrich (further details will be provided in Section B). Other than conducting research, the researchers also craft projects for us where the data collected may then be used for their lectures or research papers. B.2 Our Attachment Work Schedule at NTU, SPMS • Week 1: Background Reading on Organic Chemistry in TJC For Week 1 of our attachment, NTU was not ready to conduct our attachment as their new SPMS building was not yet ready. As a result, my teammates and I were expected to report to college everyday to do research and read up on topics related to Organic Chemistry (mentioned in description of our attachment in WOW! 08 handout when we chose our attachment choices). Also, we did revision on what we learnt regarding Organic Chemistry in Year 2: Hybridization. (For information on hybridization, please refer to Section A.1 of this report) The following are topics we researched on during Week 1: - What is Organic Chemistry? - Importance of Chemistry in our lives - Alkanes and Aromatic Hydrocarbons (Benzene and Alkylbenzene) - Mechanism of reactions involving different types of organic compounds 5 Girish constructing diagrams of organic compounds for Prof. Loh’s lecture
  • 6. - Research projects under Prof. Loh’s charge - Green Chemistry: The Twelve Principles of Green Chemistry Two group meetings were also held to ensure clear understanding of our attachment and the central theme of research at NTU. My teammates and I regarded group meeting to be proper platforms for discussion and gathering of useful information for our attachment. For the first meeting, each member was also assigned a specific topic for further research and reading from the list of research projects under Prof. Loh’s charge. During the second meeting, each member presented his/ her findings on the topics they were assigned to previously. Also, we even branched out to work on difficulties met and solutions to them. Our first Conferencing Friday was held on 11 January 2008. We had a small meeting with our teacher mentor, Mr Terence Ong to discuss our progress at attachment and his work expectations of us. Also, we were given instructions regarding our attachment at NTU on next Monday. There was also clarification of problems faced and their solutions. • Week 2: Practice on Use of Software (i.e. ChemDraw and SciFinder) Our attachment at NTU officially began on Monday, 14 January 2008. Firstly, we were given a brief tour around the new SPMS building by Prof. Loh. The new SPMS building contained specially designed laboratories, study rooms with state-of-the-art facilities and other rooms specifically used for equipment storage. Each storey of the new SPMS building is meant for a specific area of research. For instance, all laboratories conducting Biological Chemistry related research are located on the first storey. 6 Cycloalkanes, a type of alkanes Benzene, an Aromatic Hydrocarbon Organic Chemistry Research Laboratory
  • 7. The picture on the left is one of the Organic Chemistry research laboratories which were not yet in use by the researchers then. 7
  • 8. For Week 2 and 3, my team and I worked in another faculty, NTU School of Material Sciences and Engineering for attachment. For the first half of Week 2, we mainly focused on learning two programs, widely used by researchers and students at NTU, ChemDraw and SciFinder. As the details of our final project were given to us on Wednesday, we spent the next two days of Week 2 using SciFinder to work on our final project. ChemDraw ChemDraw is a major chemical drawing program that enables stereochemistry recognition and display, multi-page documents and professional structure drawing. It is the software NTU professors use to construct diagrams of chemical reactions and structures of molecules in preparation for their lectures. ChemDraw enables perfect structure drawing of molecules and prevents untidiness. The diagrams drawn can be duplicated for further use in the future by saving the picture file. After mastering the basics, we also moved on to draw molecules with more complicated structures and chemical reactions involving these complicated molecules. 8 Complex molecular structure under construction
  • 9. 9 Chemical reaction involving molecules with complex structures
  • 10. SciFinder SciFinder is a program used by universities and other academic institutions to increase convenience for multi-database searching. SciFinder enables users to gain access to references of a research topic from well-known databases all over the world, such as American Chemical Society and Wiley InterScience. We can further sort the search results by adding criteria (e.g. publication year and author name). Even if we need to gain urgent access to publications by a certain author or database, we can do so easily. This greatly improves convenience and saves time. One notable point is that SciFinder is also designed with a graphic interface; hence enabling structure drawings done by the user to be used as a reaction query for explore single- or multi-step reactions involving that substance-of-interest. Moreover, we can also gain access to further details regarding the substance-of-interest (which can take the form of a reagent, reactant, product, solvent or catalyst). The picture of the left shows the substance-of-interest as a reactant about to be used as search query to search reactions it was involved in. 10 Substance-of-Interest drawn as a reaction query Search results arranged according to a specific publication year
  • 11. Moreover, SciFinder can be used to identify a certain substance-of-interest and at the same time, provide further details on it. By entering any chemical name of the substance or its CAS Registry Number, we will be able to gain access to its CAS Registry record. The CAS Registry record of a substance is a record which contains property data of that substance. An example of a CAS Registry record found in SciFinder can be seen in the picture below. (Note: CAS registry numbers are unique numerical identifiers for chemical compounds, polymers, biological sequences, mixtures and alloys.) 11 CAS Registry record (property data) of a substance-of-interest
  • 12. For SciFinder, the researchers would usually select lists of online references from their handouts on Organic Chemistry for us to search for the PDF documents of those references. We would then label those documents before saving them in a folder on Desktop. Sometimes the online references given to us contained data on chemical reactions they were interested in exploring on then, locating and saving the data in the computer would save them the trouble of searching for those resources again. We also had our second Conferencing Friday. We mainly gave feedback onour attachment, what we have learnt so far and what we hoped to see improvement in. We also sought help from our teacher mentor Mr Ong on the project given to us by our researchers in NTU. Our attachment ran smoothly, hence it was a rather brief meeting. • Week 2 & 3: Application of SciFinder to Final Project - Chiral Synthesis After learning how to use ChemDraw and SciFinder, we were assigned our final project to work on for the rest of Week 2 and 3. However, we encountered some difficulties (to be elaborated in Section D) which greatly shortened the amount of time available to work on our project. Basically, we were given the chemical structure of a certain substance (Compound B) which we were supposed to identify and look up chemical reactions involving it. In the process of researching chemical reactions involving Organic Compound B, we should also identify possible ‘Reactant A’s and ‘Product C’s. However, it is important to note that Reactant A must contain at least one double bond but not any aromatic rings. Suggested plan to carry out research: 1) Identify full structure of Organic Compound B. From there, obtain its full chemical formula to retrieve information on its properties and chemical reactions involving it. 2) Properties of Organic Compound B can be obtained from the Internet. Chemical reactions involving Organic Compound B can be retrieved from SciFinder. 12 Product C+Reactant A Organic Compound B Tasks: Make use of the given chemical structure to identify Organic Compound B Identify possible ‘Reactant A’s and ‘Product C’s Identify underlying mechanism of these chemical reactions
  • 13. We discovered that Organic Compound B contains four functional groups known as methyl groups. Each methyl group has a chemical formula of CH3, thus we came to the conclusion that Organic Compound B has a chemical formula of C12H24B2O4. After obtaining the chemical formula of Organic Compound B, we proceeded to research on chemical reactions involving it using SciFinder. To do this, we used the graphic interface in SciFinder to find chemical reactions involving Organic Compound B. We drew the structure of Organic Compound B and a double bond (having labelled them as ‘Reactant/ Reagent’). Below are some criteria we included to filter our search results. Search results should contain: • Product to be of a substructure of a more complex structure • Only single-step catalyzed reactions • Research papers published in the year 2007 We found 16 search results which fit the criteria in total. As we were clueless about the underlying mechanism of the chemical reactions, we sought help from our supervisor and discovered that the underlying mechanism was Chiral Synthesis. We proceeded to do some research on the topic of Chiral Synthesis. (Note: The topic of Chiral Synthesis will be discussed in Section C) Finally we compiled all the information we obtained into a PowerPoint presentation and handed it in for file check by Mr Ong on our third Conferencing Friday. (PowerPoint Presentation can be found in WOW! 08 File ‘Attachment Work’ folder) 13 Hand drawn chemical structure (search query in SciFinder)
  • 14. Me Me Me Me Me Me Me Me B O O B O O (Step 1.2) + CH CH3C CH2 (Step 1.2) 1.2 S:PhMe, 14 h, rt 1.1 C:213843-90-4, C:Ph2-pentadienone Pd, S:PhMe, 1 h, rt Me Me Me Me Me Me Me Me Me B CH2 B O O O O R 68% NOTE: stereoselective, Reactants: 2, Catalysts: 2, Solvents: 1, Steps: 1, Stages: 2 Catalyst Reactant A Catalyst Meanwhile, below are some examples of search results we obtained: • Reaction 96 • Reaction 123 14 Me Me Me Me Me Me Me Me B O O B O O (Step 1.2) + Ph CH C CH2 (Step 1.2) 1.2 24 h, rt 1.1 C:913706-72-6, C:Ph2-pentadienone Pd, S:PhMe, 1 h, rt Me Me Me Me Me Me Me Me Ph B CH2 B O O O O S 53% NOTE: stereoselective, optimized on catalyst, Reactants: 2, Catalysts: 2, Solvents: 1, Steps: 1, Stages: 2 Reactant A Organic Compound B Product C (% symbolizes effectiveness of catalyst) Other information about this reaction Organic Compound B Product C (% symbolizes effectiveness of catalyst) Other information about this reaction
  • 15. • Week 4: Preparation of Prof. Loh’s Lecture and Chemical Lists Preparation of Prof. Loh’s lectures: For Week 4, the new SPMS building was finally ready for use. Thus our attachment was no longer conducted at NTU School of Material Sciences and Engineering, but at the new School of Physical and Mathematical Sciences. Having mastered using ChemDraw and SciFinder, as well as finished our final project, we could help with actual work in NTU. Using ChemDraw, we constructed diagrams of chemical reactions and molecules in preparation of Prof. Loh’s lecture on ‘Catalysis and Green Chemistry’. Generally, his paper covered on several topics like the two main groups of catalysts (homogenous catalysts and heterogeneous catalysts), importance of catalysts in the manufacturing industry, and the implementation of Green Chemistry to reduce waste as a by-product by the end of a chemical reaction. Thus, the diagrams we constructed mostly depicted catalyzed biological reactions. 15
  • 17. Preparation of Chemical Lists: As mentioned in Section B.2, SciFinder can be used to identify a substance-of-interest through its name or CAS Registry number and provide further details on it. By entering the chemical name of any substance or its CAS Registry Number, we could gain access to its CAS Registry record. However, we discovered that a website ‘Sigma Aldrich’ is also capable of doing so. Sigma Aldrich has similar functions as SciFinder, except that chemists could even order chemicals in specific amounts they needed online. This is comparatively more convenient than SciFinder. Screenshot of Sigma-Aldrich and its functions Below is an extract from one of the chemical lists we prepared: Name CAS Original pathalic anhydride [85-44-9] 1kg Triethyl orthoformate [122-51-0] 1.01 * 3 methyl acrylate ee90 [96-33-3] 1.01 Vinyl acetate [108-05-4] 1.01 * 2 Methyl bromoacetate [96-32-2] 500ml Trimethylactic anhydride ee90 [1538-75-6] 100g Maleic anhydride [108-31-6] 1kg sodium α-ethylhexanoate [19766-89-3] 1l 4-Methylcinnamic acid [1866-39-3] 20g Methyl 2-bromopropionate [5445-17-0] 5.0mL α-bromobutyric acid p890 [80-58-0] 80ml We also had our very last Conferencing Friday for our attachment. Generally, there was discussion on deadlines for our WOW! 08 files and we were free to ask any questions we had regarding the contents of our reports and WOW! 08 files. 17
  • 18. An illustration of chirality in D-Alanine and L-Alanine C. Final Project on Chiral Synthesis C.1 What is Chiral Synthesis? Chiral Synthesis is in essence organic synthesis that introduces one or more new desired elements of Chirality. Chiral synthesis is very important in the pharmaceutical field, especially when it comes to manufacturing of drugs. Different enantiomers have different biological activity; this is why side effects of drugs arise. Due to the problem of side effects, an external factor has to be introduced such that chiral synthesis occurs, thus forming a chiral product which counters the side effects. Chirality is an asymmetric property that refers to the inability of an object to superimpose on its mirror image. Enantiomers are stereoisomers which are non-superimposable on each other, just like human hands. The right hand is non- superimposable on the left hand; no matter how the two hands are placed together, not all major features of both hands coincide. They have their ‘handedness’, which is similar to chirality in molecules. 18 Chirality of our human hands
  • 19. C.2 Relation of Chiral Synthesis to our project Chiral synthesis is important in the chemical reaction which we were supposed to research on as it helps to break the B-B bond of Organic Compound B, thus enabling the boron to attack another reactant and form a new product. Initially the reactant was achiral, but after the introduction of a chiral catalyst, the product formed was chiral. For the diagram below, we can see that Organic Compound B was a chiral molecule whereas Reactant A was an achiral molecule initially. By introducing an external factor (i.e. a chiral catalyst) into the chemical reaction, organic synthesis occurs. As a result, Product C formed is a chiral molecule. A double bond is broken from Reactant A (H3C – CH = C = CH2) and the B - B bond in Bis (pinacolato) Diboron molecule. In the presence of catalysts, the double bond between C and CH attacks the B-B bond, forming a new single bond between boron and carbon, as well as a double bond between CH2 and C. 19 Me Me Me Me Me Me Me Me B O O B O O (Step 1.2) + CH CH3C CH2 (Step 1.2) 1.2 S:PhMe, 14 h, rt 1.1 C:213843-90-4, C:Ph2-pentadienone Pd, S:PhMe, 1 h, rt Me Me Me Me Me Me Me Me Me B CH2 B O O O O R 68% NOTE: stereoselective, Reactants: 2, Catalysts: 2, Solvents: 1, Steps: 1, Stages: 2 Organic Compound B Reactant A Catalyst Product C (% symbolizes effectiveness of catalyst) Other information about this reaction Chiral synthesis of organic compounds in Reaction 123
  • 20. D. Other Lessons Learnt D.1 Organic Chemistry Laboratory Technique: Extraction In organic chemistry labs, liquid-liquid extractions are always performed using a separatory funnel. During extraction, two immiscible liquids (forming separate layers when mixed) will be mixed inside the separatory funnel and left to settle. Eventually two layers will be formed again at the end of the mixing process. One is the aqueous layer while the other is the organic layer. The aqueous layer and organic layer are to be contained in different beakers. The layer with the higher density flows through the stopcock down the separatory funnel into the beaker while the layer with lower density has to be poured from the top of the separatory funnel into another beaker to prevent contamination. Self-Notes: √ Sometimes during mixing, an emulsion may be observed as the boundary between the aqueous and organic layers might be unclear. We can add another external agent to increase polarity to one of the layers, so as to increase the difference in polarity between the two layers. This ensures that the two layers are more likely to be immiscible, thus lowering chances of observing an emulsion. √ DO NOT label the beakers containing the two layers as ‘bottom layer’ and ‘top layer’. This is because the top and bottom layers might change over time. Be specific; label them as aqueous layer and organic layer. √ DO NOT transfer the layer with lower density into a beaker by letting it flow down the separatory funnel as this may result in serious contamination. 20 A separatory funnel Supervisors carrying out extraction process
  • 21. D.2 Organic Chemistry Laboratory Technique: Column Chromatography 21 Silica Gel Organic Compound Column chromatography in process Column chromatography is one of the most commonly conducted experiments at NTU. Its one of the most important experiments to chemists doing Organic Chemistry research. Column chromatography is used to purify chemical compounds from a mixture of compounds. In column chromatography, a layer of sand is topped to protect the organic compound from the velocity of newly added eluent. Eluent is apure solvent or a mixture of solvents added into the column to flow down it. As eluent enters the column and flows through the silica gel, it flows down much faster than the organic compound. The purpose of silica gel is to act like a filter to prevent unwanted chemicals from entering and flowing down the column as this changes the rate of reaction. As different chemicals react differently to silica gel, the rate at which they flow down the column is enough to determine the type of compounds they are. Different sizes of columns used to contain different amounts of compounds
  • 22. D.3 Organic Chemistry Laboratory Equipment – Rotatory Separator Function: The rotatory separator helps to separate impure solutions into solute (desired product) and solvent which is poured away into large containers to be disposed of at the end of the process. How to use the Rotatory Separator: 1) Inside the container, a water bath is set at the boiling point of the impure solution. 2) When the round-bottomed flask containing the impure solution is added to the water bath, the flask spins and heat is transferred to all parts of it evenly. 3) The spinning of the round-bottomed flask prevents heat from being applied to a concentrated point which might result in spillage of the impure solution. 4) Spinning increases the rate of reaction within the round-bottomed flask. 5) As the impure solution is heated to its boiling point, it evaporates, rises upwards as hot air, gets into contact with the condenser and the solvent condenses. The solvent flows down the condenser and is collected into another round bottomed flask. 6) At the end of the experiment, the solute will be used for other experiments while the solvent will be considered as a toxic waste product to be thrown away. 22 Waste solvent after experiment
  • 23. E. Difficulties Faced and Solutions to Them E.1 Deciphering Technical Terms While carrying out our research on Organic Chemistry, we encountered many technical terms which we could not comprehend. Some of these technical terms include chirality, enantiomers and enantioselective reactions. What I did was to record down these technical terms just in case we encounter them during attachment. In the meanwhile, I carried out some research on these technical terms to seek a simpler explanation of these technical terms. However, I realized that at times the search results obtained were mostly research papers containing complicated information related to these technical terms. Also, I encountered some of the technical terms mentioned above such as chirality and enantiomers while conducting research for the final project on Chiral Synthesis. With the help of my other groupmates and supervisors at NTU, I managed to have a clearer idea of what those technical terms stand for. Also, I managed to apply the new concepts I have learnt to use when I attempted to explain the underlying mechanism of chemical reactions. E.2 Working on Wrong Compound for Final Project In the course of carrying out research for our final project on Chiral Synthesis, we received the wrong information and thus worked on the wrong compound for our final project. Instead of Bis (pinacolato) Diboron (Chemical formula: C12H24B2O4) which we were supposed to work on, we worked on another compound Carapine Alkaloid (Chemical formula: C10H28O4). As a result, we were left with four days to work on our final project (instead of the second half of Week 2 and the whole of Week 3). Having lost one third of the time to working on something irrelevant, my groupmates and I had no choice but to push ourselves harder. We had to approach our supervisor for the full name of Organic Compound B instead of finding it out ourselves. However our supervisor was very 23 Product C+Reactant A Organic Compound B
  • 24. understanding and in fact guided us by dropping some more clues for our project. Thus, we were able to finish our project on time for submission. 24
  • 25. F. Conclusion On the whole, I believed I have benefitted very much from this attachment, both intellectually and psychologically. In terms of knowledge, I have gained much valuable knowledge on Organic Chemistry, especially in the area of Chiral Synthesis. Also, I have had a clearer idea of how research is carried out in Organic Chemistry laboratories at NTU and better understanding of Organic Chemistry laboratory techniques. In terms of psychological benefits, I have had the opportunity to work with researchers from one of the most well-known universities in the region before my peers. Also, I have experienced a very different learning style from what I have experienced in Temasek Academy. Moreover, I have gained greater insight on working with others in a group as well as others from different nationalities. Many thanks to: At NTU Professor Loh Teck Peng, Dr. Lu Jun, Mr Wang Peng, Mr Xu Yunhe and other researchers at NTU At TJC Mr Simon Foo, Mr Terence Ong and not forgetting, my groupmates consisting of Wanshi, Eran, Sadia and Girish Thank you very much for your kind guidance and participation in what has been a very enriching and memorable attachment for me. Thank you very much! 25