Total Synthesis of Indolizidine Alkaloids (-)-167B, (-)-209I, and (-)-223A by Using a Common Tricyclic Lactone

Stereodivergent Synthesis of Alkaloid (±)-223A and (±)-6-epi-223A via Rh-Catalyzed Hydroformylation Double Cyclization

A stereodivergent approach toward total syntheses of Dendrobatid alkaloids 223A and 6-epi-223A is described. The approach features a concise construction of an indolizidine skeleton by Rh-catalyzed domino hydroformylation double cyclization and sequential stereocontrolled transformations such as reductive alkylation or anti-selective α-alkylation of the 5-oxoindolizidine. These stereoselective reactions afford the desired stereochemistry in the targets.

One-shot access to isoquinolone and (hetero)izidinone architectures using cyclic α-chloro eneformamides and cyclic anhydrides

A site-selective annulation reaction between cyclic α-chloro eneformamides and cyclic anhydrides which provides direct and modular access to pharmaceutically pertinent izidinones and isoquinolones, is presented.