Synthesis of oxazoles from O-trimethylsilyl acyltrimethylsilane cyanohydrins
摘要:
Sequential addition of organolithium reagents and acyl chlorides (or anhydrides) to O-trimethylsilyl acyltrimethylsilane cyanohydrins affords beta-(acyloxy)-N,N-bis(trimethylsilyl) enamines which cyclize to substituted oxazoles under thermolysis or treatment with trimethylsilyl trifluoromethanesulfonate. Oxazoles were prepared containing alkyl and phenyl substituents at C-5, alkyl, alkenyl, and phenyl substituents at C-4, and alkyl, alkenyl, phenyl, and functionalized substituents at C-2.