In each reaction box, place the best reagent and conditions from the list below. 3-Hexanone should be the exclusive final product

In each reaction box, place the best reagent and conditions from the list below. 3-Hexanone should be the exclusive final product. (A reagent may be used more than once.)

Concepts and reason
Synthesize ketones form alkynes by using the list of reagents provided. Hydration of alkynes form ketones.

Fundamentals
Given alkyne can be converted to ketone by using the following steps.

  1. Deprotonation and reaction with alkyl halide
  2. Hydration of alkyne

Answer:

The reaction is,

Ethyne reacts with strong base imageto form ethyn-1-ide.
Bromine atoms leaves with pair of electrons from ethyl bromide followed by nucleophilic attack of ethyn-1-ide to form but-1-yne.

The reaction is,

But-1-yne reacts with strong base image to form but-1yn-1-ide.
Bromine atoms leaves with pair of electrons from ethyl bromide followed by nucleophilic attack of but-1yn-1-ide to form hex-3-yne.

The reaction is,

image

image

Thus, the correct choice of reagents is,

image