Manganese(III)-promoted highly stereoselective phosphorylation of acyclic tertiary enamides to synthesize E -selective β-phosphoryl enamides.

A concise manganese(III)-promoted stereoselective β-phosphorylation of acyclic tertiary enamides and diverse H-phosphine oxides was achieved. This reaction proceeds with absolute E -selectivity in contrast to Z -selectivity obtained in other previous works and affords various E -selective β-phosphorylated tertiary enamides in high efficiency. To the best of our knowledge, this is the first case of E -selective β-phosphorylation of tertiary enamides through C-H functionalization. In addition, the method features broad substrate scope, good functional group compatibility and efficient scale-up.