Rh-Catalyzed cyclization of 2,3-allenoic acids in the presence of 2,3-allenols

Herein we report a [Cp*RhCl2](2)-catalyzed coupling cyclization of two different classes of allenes with 2,3-allenoic acids affording 2(5H)-furanone skeletons of products and 2,3-allenols forming a conjugated (E)-enal or enone functionality to the beta-position of the 2(5H)-furanones. These products are important building blocks for the syntheses of potentially bioactive compounds. The reaction proceeded via the nucleometalation, insertion, and stereodefined 1,4-H delivery carried by rhodium.

Automated summary

A novel synthetic method was reported for the coupling cyclization of different classes of allenes with 2,3-allenoic acids catalyzed by rhodium, leading to the formation of compounds with important bioactive components. The reaction involved nucleometalation, insertion, and stereodefined 1,4-H delivery processes carried out by the rhodium catalyst.