Answer Happy

X pk, The acidity of the a-proton on a carbonyl compound depends on the structure of the carbonyl compound. H 16.7 Ph 18.3 B :0 H CH3 19.3 B-H H X Х H OCH2CH3 24 H H NH2 25 a) Which of the functional groups represented here has the least acidic alpha proton? Which has the most acidic alpha proton? Explain how you determined this from the information provided. The C=0 carbon of all carbonyl compounds is electrophilic (partially-positive). The magnitude of this partial-positive charge depends on the substituents on the carbonyl. The aldehyde has the largest 8+ carbon; the 8+ on the ketone is smaller and the 8+ on the ester is even smaller. H H when one more H 8+ CH3 H3C 8+ CH3 H3C 8+ CH3 b) Use inductive effects to explain why the aldehyde carbonyl carbon is more s+ than the ketone carbonyl carbon. c) Use inductive and resonance effects to explain why the ester carbonyl carbon is less 8+ than the ketone carbonyl carbon. d) Which of the compounds from part b) (ethanal, propanone, and ethyl ethanoate) would react the fastest with a given nucleophile? Explain.