17.33(a)The bacterial enzyme cyclohexanone monooxygenase was described in Section 17.16 as ableto catalyze a biological Baeyer–Villiger reaction. Compound A is 4-methylcyclohexanone.(b)The product of Baeyer–Villiger oxidation of 4-methylcyclohexanone with peroxyacetic acidwould be the racemic cyclic ester (lactone), not the single enantiomer shown in part (a) fromthe enzyme-catalyzed oxidation.17.34(a)Nucleophilic ring opening of the epoxide occurs by attack of methoxide at the less hinderedcarbon.The anion formed in this step loses a chloride ion to form the carbon–oxygen double bond ofthe product.(b)Nucleophilic addition of methoxide ion to the aldehyde carbonyl generates an oxyanion,which can close to an epoxide by an intramolecular nucleophilic substitution reaction.The epoxide formed in this process then undergoes nucleophilic ring opening on attack by a
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