Enantioselective construction of functionalized oxazoles via anionic stereogenic-at-cobalt(iii) complex-catalyzed Ugi-4CR/Wittig reaction sequences

Abstract

A one-pot synthesis of chiral multifunctional oxazole frameworks is accomplished via a cascade reaction involving an anionic stereogenic cobalt(III) complex-catalyzed enantioselective Ugi four-component/Wittig process. This approach tolerates a complex reaction system that includes aldehydes, amines, carboxylic acids, and isocyano-(triphenylphosphoranylidene)acetates, yielding chiral 2,4,5-trisubstituted oxazoles with good enantioselectivities (up to 93 : 7 er).