Question

Drawing appropriate structures or mechanisms is essential to answer the following

a. Why shouldn't you use ethanol as a solvent for Grignard reactions?

b. Why don't we usually obtain a 100% racemization from an SN1 reactions?

c. Ethers have relatively lower boiling points compared to corresponding alcohols(same # of carbons). Why?

d. SN2 reactions need to be carried out in aprotic polar solvents. Why?

e. In Butan-2-one, show the most acidic and least acidic protons. Explain why.

f. Explain why addition of one mole of Br2 to buta-1,3-diene at high temperature gives 1,4 dibromo but-2-ene.

Answer 1

Explanation of

c C2H5OH and CH3OCH3 have difference in the boiling point due to the intra molecular hydrogen is bonding in alcohol. It is absent in ether.

d In SN2 reaction the polar aprotic solvent solvate the nucleophile and increase the nucleophilicity.