Question

Question #c84fc

Answer 1

It is probably a matter of cost of the acetyl halide.

Explanation:

All three compounds readily react with amines per the equation

`"RNH"_2 + "CH"_3"CO-X" → "RNH-COCH"_3 + "HX"`

The prices of the halides in US dollars are approximately

`"CH"_3"COCl"color(white)(m)"$100/L"`
`"CH"_3"COBr"color(white)(m)"$300/L"`
`"CH"_3"COF"color(white)(mll)"$700/L"`

Chemists like to choose the cheapest reactant that will do the job.

Hence, acetyl chloride is the reagent of choice.