PROBLEM 7.79

Question

Question: Draw a stepwise mechanism for the following reaction sequence.

Step-by-Step Solution

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Answer

1Ketone

A ketone is represented by the functional group -CO-. The carbonyl carbon is an electrophilic center of the ketone where the nucleophile can attack.

2Chemical properties of ketone

The ketone also contains acidic hydrogen adjacent to the carbonyl carbon. Therefore, a base can abstract and form the carbanion.

3Explanation

In the given reaction, the acidic hydrogen of hexanone is abstracted by the given base NaH. Therefore, the carbanion delocalizes its electrons. The two resonating structures give the two products.

The major product is formed by the pi donation of an electron to the methylbromide.

The minor product is formed by the oxide donation of electrons to the methylbromide.

Representation of the first step

Representation of the second step

PROBLEM 7.78

6-11P

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