Reactions of arenediazonium tetrafluoroborates with 3-chloro-2-methylpropene in the presence of potassium chloride, bromide, and thiocyanate

Arenediazonium tetrafluoroborates reacted with 3-chloro-2-methylpropene in the presence of potassium chloride, bromide, and thiocyanate to give the corresponding 1-aryl-3-chloro-2-halo(thiocyanato)-2-methylpropanes. The presence of a copper salt is a necessary condition for the reaction to occur. The yields of the corresponding 1-aryl-3-chloro-2-halo-2-methylpropanes in the Meerwein reaction were approximately twice as low. Introduction of a methyl group to C(2) in the 3-chloropropene molecule does not change the reaction regioselectivity.