Question

A ${{2}^{0}}$ alcohol as shown can be obtained by the reaction of di-t-butyl ketone and:
a.) Isopropyl magnesium bromide
b.) t-butyl magnesium bromide
c.) EtMgBr
d.) MeMgBr

Answer 1

Hint: Secondary alcohol is a compound in which the hydroxyl group that is a $-OH$ group is attached to a saturated carbon which also has two other carbons attached to it. A saturated carbon is a carbon which is bonded to other atoms by a single bond.

Complete step by step answer:
The di-t-butyl group is a bulky group and due to the steric hindrance of the di-t-butyl group in ketone the group containing bulky group or the group having beta hydrogen does not react with it which means that (${{3}^{0}}$) tertiary alcohol cannot be obtained.
But if there is transfer of hydride ion i.e. ${{H}^{-}}$ from the beta position of the RMgX group to the $C=O$group takes place then there is formation of cyclic transition state which produce secondary alcohol and alkene.
Hence MeMgBr does not react with di-t-butyl ketone which means that it will not produce secondary alcohol and alkene.
Reactions involves is shown below:

Hence the correct answer is option (A), option (B) and option (C) i.e. A ${{2}^{0}}$ alcohol can be obtained by the reaction of di-t-butyl ketone and, Isopropyl magnesium bromide, t-butyl magnesium bromide, EtMgBr.
So, the correct answer is “Option A,B and C”.

Note: Alcohol is a homologous series having the functional group $-OH$ also known as hydroxyl group. The general molecular formula for alcohols is ${{C}_{n}}{{H}_{2n+1}}OH$. The secondary alcohol isopropanol is a very important chemical which is used for the sustainable production of fuels and some other substances. Secondary alcohol can be oxidized to aldehydes and ketones using jones reagent.