Divergent alkynylative difunctionalization of amide bonds through C-O deoxygenation versus C-N deamination.

The transformation and utilization of amides are significant in organic synthesis and drug discovery. Here we demonstrate a divergent alkynylative difunctionalization of amides in a single transformation. In this reaction, amides react with an organometallic nucleophile to form a tetrahedral intermediate. By altering the N-substitution or the acyl group, the tetrahedral intermediate species selectively undergoes C-O or C-N cleavage with a concomitant capture by an alkynyl nucleophile generated in situ. This process enables the selective introduction of two different functional groups into the amide molecular architecture, producing valuable propargyl amine and propargyl alcohol products. The selectivity between deoxygenation and deamination process has been further elucidated by DFT calculations. Overall, this reaction successfully transforms the traditional mode of nucleophilic acyl addition to amides to a divergent C-O/C-N cleavage. The particularly wide substrate scope, including late-stage modification of bioactive molecules, demonstrates its potential broad applications in organic synthesis.