The carbonyl stretch of acetyl chloride (CH3COCI) is found at 1806 cm-1. Is the C=0 bond stronger or weaker than the one in an amide? What does this suggest about the resonance contribution of a lone pair on Cl in an acid chloride compared to that of the lone pair on N in an amide? Explain. Hint: See Problems 15.43 and 15.44. Problem 15.43 calls attention to a resonance structure of an amide that accounts for the lowering of the C=0 stretch frequency. An analogous resonance structure can be drawn for an ester. (a) Draw that resonance structure for methyl acetate (CH3CO,CH3). (b) Based on the fact that an ester's c=0 stretch frequency is higher than an amide's, does that resonance structure have a larger contribution toward the resonance hybrid of an ester or an amide? Using arguments of charge stability, explain why that should be so.

The carbonyl stretch of acetyl chloride (CH3COCI) is found at 1806 cm-1. Is the C=0 bond stronger or weaker than the one in an amide? What does this suggest about the resonance contribution of a lone pair on Cl in an acid chloride compared to that of the lone pair on N in an amide? Explain. Hint: See Problems 15.43 and 15.44. Problem 15.43 calls attention to a resonance structure of an amide that accounts for the lowering of the C=0 stretch frequency. An analogous resonance structure can be drawn for an ester. (a) Draw that resonance structure for methyl acetate (CH3CO,CH3). (b) Based on the fact that an ester's c=0 stretch frequency is higher than an amide's, does that resonance structure have a larger contribution toward the resonance hybrid of an ester or an amide? Using arguments of charge stability, explain why that should be so.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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