Synthesis and Reactions of 2,2-Dichlorocyclopropylmethyl-4-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)benzoate with Secondary Amines

Abstract

The reaction of potassium 4-aminobenzoate with 2-bromomethyl-1,1-dichlorocyclopropane proceeds regioselectively with the retention of a three-membered ring and leads to the formation of 2,2-dichlorocyclo-propylmethyl 4-aminobenzoate. The reaction of 2,2-dichlorocyclopropylmethyl 4-aminobenzoate with maleic anhydride and intramolecular cyclization of the resulting amide in the presence of p-toluenesulfonic acid yields 2,2-dichlorocyclopropylmethyl-4-(2,5-dihydro-2,5-dioxo-1H-pyrrol-1-yl)benzoate. Secondary amines are attached at the double bond of the synthesized maleimide with the formation of 2,2-dichlorocyclopropylmethyl-4-[(3-R₂N-2,5-dioxo-2,3,4,5-tetrahydro-1H-pyrrolyl)]benzoates.