Tandem cycloaddition–decarboxylation of α-keto acid and isocyanide under oxidant-free conditions towards monosubstituted oxazoles†
Abstract
An efficient method, tandem [3 + 2] cycloaddition–decarboxylation of α-keto acid and isocyanide promoted by copper salt, has been developed. Under oxidant-free conditions, a series monosubstituted oxazoles have been constructed. Different from the traditional application of α-oxo acids as acyl surrogates, the elegant approach herein ingeniously avoids consuming excess oxidants.