Identify the coupling partners that can be used to prepare the following compound in a Heck reaction.
A) ethyl vinyl ketone and p-methylstyrene
B) ethyl vinyl ketone and 4-iodotoluene
C) p-methylstyrene and propionoyl chloride
D) (
E)-1-(2-bromovinyl)-4-methylbenzene and propionoyl chloride

Question

Identify the coupling partners that can be used to prepare the following compound in a Heck reaction. 
A) ethyl vinyl ketone and p-methylstyrene 
B) ethyl vinyl ketone and 4-iodotoluene 
C) p-methylstyrene and propionoyl chloride 
D) (
E)-1-(2-bromovinyl)-4-methylbenzene and propionoyl chloride

Quizplus · Accepted Answer

In a Heck reaction, a palladium catalyst is used to couple an alkene with an aryl halide. Option A has an aryl compound (p-methylstyrene) but the alkene partner is not an aryl halide. Option C has an alkene partner (p-methylstyrene) but the other partner is not an aryl halide. Option D has an aryl halide (2-bromovinyl) but the alkene partner is not compatible. Only option B contains an aryl halide (4-iodotoluene) and an alkene partner (ethyl vinyl ketone) that are both suitable for a Heck reaction. Therefore, option B is the best choice.

Identify the Coupling Partners That Can Be Used to Prepare