Solid phase synthesis of isoxazole and isoxazoline-carboxamides via [2+3]-dipolar cycloaddition using resin-bound alkynes or alkenes

Abstract

An efficient approach for the parallel solid phase synthesis of isoxazole and isoxazoline derivatives has been developed. The isoxazoles and isoxazolines were constructed through a 1,3-dipolar cycloaddition reaction of nitrile oxides, with resin-bound alkynes or alkenes. The cycloaddition reaction conditions performed on solid phase supports was optimized, and an array of resin-bound carboxylic acid building blocks was utilized for distinct conversions. This methodology presents a new alternative to the diversity oriented synthesis of disubstituted isoxazoles and isoxazolines different from existing routes which are limited in structural diversity.