Phosphine-Catalyzed Synthesis of 1,3-Dihydro-3-alkylidene-2H-indol-2-ones

A P(4-OMe-C6H4)(3)-catalyzed Michael addition/double bond migration tandem reaction between allenyl imide and indol-2-ones was developed. This synthetic strategy for diverse 1,3-dihydro-3-alkylidene-2H-indol-2-ones features operationally simple, good substrate scope, high chemoselectivity and mild reaction conditions. The proposed reaction mechanism is also provided.

Automated summary

A P(4-OMe-C6H4)(3)-catalyzed Michael addition/double bond migration tandem reaction between allenyl imide and indol-2-ones has been developed. This synthetic strategy allows for the synthesis of diverse 1,3-dihydro-3-alkylidene-2H-indol-2-ones and features operationally simple procedures, good substrate scope, high chemoselectivity, and mild reaction conditions. The proposed reaction mechanism is also elucidated.