Question

In the reaction sequence,

the product (B) is:

Answer 1

Cyclohexane

Answer 2

Cyclohexanone undergoes reaction with ethanethiol ($HSCH_2CH_3$) in the presence of an acid catalyst ($H^+$) to form the corresponding dithioacetal (A). This dithioacetal is then reduced by hydrogen gas in the presence of a nickel catalyst (Raney nickel) and heat. This process, known as desulfurization, cleaves the C-S bonds and replaces them with C-H bonds, converting the dithioacetal functional group ($C(SR)_2$) into a methylene group ($CH_2$). Therefore, the carbonyl group of cyclohexanone is effectively reduced to a methylene group, yielding cyclohexane as the final product (B).