Which of the following combinations give cycloheptanone as the main product?

Acyclopentanone with $CH X_{2} N X_{2}$ in ether
B1-(aminomethyl)cyclohexan-1-ol with $NaNO X_{2}$ / $HCl$
Ccyclohexanone with $CH X_{2} N X_{2}$ in ether
Dcyclohexylamine with $NaNO X_{2}$ / $HCl$

Answer: B, C

The first is a Tiffeneau-Demjanov ring expansion, and diazomethane inserts a

CH X_{2}

into cyclohexanone by the same type of migration, so both give the seven-membered ketone. Cyclopentanone with diazomethane gives cyclohexanone. Cyclohexylamine gives a diazonium ion without ring expansion, giving cyclohexanol and cyclohexene.

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