Abstract: In the preparation of olefin derivatives having an ester group at the allylic position (hereinafter referred to as "allylic ester(s)") which comprises reacting an olefin having at least one hydrogen atom at the allylic position and which will produce an allylic ester having an asymmetric carbon atom with an organic peroxide in the presence of a copper catalyst, a method for producing optically active allylic esters characterized by using, as the copper catalyst, an optically active copper complex derived from an optically active compound selected from the group consisting of Schiff's bases of the formula: ##STR1## and amino acids of the formula: ##STR2## wherein R.sub.0 is an optically active alkyl, cycloalkyl, aralkyl or aryl group which may contain an unsaturated bond and/or a substituent having a hetero atom, X and Y are each a hydrogen atom, an alkyl, cycloalkyl, aralkyl or aryl group, or a substituent having a hetero atom, R.sub.1 and R.sub.

Abstract: A process for the synthesis of 1,4-haloallylic esters from conjugated dienes which comprises preparing a reaction mixture of the conjugated diene, a halogenating agent, and a carboxylic acid and then adding to said reaction mixture a catalytic amount of a strong acid having a high dissociation constant. The invention is particularly described with reference to the synthesis of isoprene-1,4-chloroacetate(1-chloro-4-acetoxy-2-methyl-2-butene) from isoprene wherein a reaction mixture is prepared of isoprene with t-butyl hypochlorite in excess glacial acetic acid, to which is added H.sub.2 SO.sub.4 followed by stirring at 50.degree. C.