Multicatalytic Synthesis of α-Pyrrolidinyl Ketones Under Pd(II)/In(III) Catalysis

Abstract

The synthesis of α-pyrrolidinyl ­ketones 3 from N-tosylpentenamines 1 and ar­enes 2 is reported via a one-pot tandem Pd(II)/In(III)-catalyzed aminochlorocarbon­ylation/Friedel-Crafts acylation process. Both terminal and non-terminal alkenes are tolerated in the reaction, with both the E- and Z-isomers giving rise to the same product diastereomer, presumably through equilibration via a retro Mannich/Mannich addition process. Cyclic olefins also ­participate in the reaction, giving rise to fused or bicyclic products. Addition of triethylsilane or chlorodimethyl­silane after completion of the tandem reaction leads to the reduced product 4 and diaryl pyrrolidine 5, respectively, providing further scope to the methodology.