Chapter 11, Problem 11.61P

Interpretation Introduction

Interpretation:

The structures of compounds J through N in the given reaction scheme are to be determined.

Concept introduction:

Vinyl chlorides are sufficiently electron rich and undergo an E2 elimination reaction when treated with an excess of a strong base such as soda amide. As the reaction medium is strongly basic, the anion of an alkyne is formed. In the second step of this reaction, water is added to yield an uncharged alkyne.

Terminal alkynes have a weakly acidic terminal hydrogen atom, which can be abstracted by a strong base such as soda amide. This will generate the anion of an alkyne. This anion act as a nucleophile and bonded to the least substituted carbon atom in the epoxide via ${\text{S}}_{\text{N}}\text{2}$ reaction. This opens the epoxide ring and results in the alcohol with the original alkyne.

Alcohols undergo ${\text{S}}_{\text{N}}\text{2}$ reactions with phosphorous halides to yield the corresponding halides. This reaction converts $\text{ROH}$ into $\text{RBr}$.

Tetrafluoromethanesulfuric acid, also known as triflic acid, and 2, 2, 2-trifluoroethanol make a strong acid that can be used as a catalyst in the acid-catalyzed hydration reactions of alkynes. In this reaction, alkynes are converted into a ketone.

Alkyl halides, when treated with a strong nucleophile, undergo an ${\text{S}}_{\text{N}}\text{2}$ reaction to yield products.