1.
please do it all or dont do it
1-47 The following compounds are listed in increasing order of acidity. In each case, the most
acidic proton is shown in red. OH NH X, pKa = 23 Y, pKa= 8.8 Z, pKa 4.2 (a) Show the
structure of the conjugate base of each acid, including any resonance forms. (b) Explain why X is
a stronger acid than W (c) Explain why Y is a stronger acid than X (d) Explain why Z is a
stronger acid than Y
Solution
(a) In compound X nitrogen is attached to carbonyl, whereas in W methyl is attached to
carbonyl, the electronegativity of nitrogen is more compare to carbon, therefore the highlighted
proton is more acidic in compound X as a result of -I inductive effect is more pronounced for
compound X
(b) in compound Y carbonyl is attached to N-OH whereas in X carbonyl is attached to NH2,
therefore the highlighted proton is more acidic as a result -I inductive effect is more for Y
compare to X, therefore acidity is more for compound Y compare to X
(c) in compound Z the highlighted proton is attached to oxygen whereas in Y the highlighted
proton is attached to nitrogen, electronegativity is more for oxygen compare to nitrogen and -I
inductive effect is more for compound Z, as a result compound Z is more acidic compare to W,
X and Y.