Rhodium-Catalyzed 1,4-Additions to Enantiopure Acceptors: Asymmetric Synthesis of Functionalized Pyrrolizidinones
作者:Ludivine Zoute、Gabriele Kociok-Köhn、Christopher G. Frost
DOI:10.1021/ol900843a
日期:2009.6.18
The rhodium-catalyzed 1,4-addition of arylboronic acids to an enantiopure heterocyclic acceptor proceeds under ligand control to effect an asymmetric synthesis of functionalized pyrrolizidinones. The protocol allows convenient access to all four stereoisomers of pyrrolizidinone 3a (Ar = Ph) by appropriate selection of substrate and catalyst.
Asymmetric synthesis of functionalized pyrrolizidines by an organocatalytic and pot-economy strategy
作者:Chia-Hsin Lin、Bor-Cherng Hong、Gene-Hsiang Lee
DOI:10.1039/c5ra25103f
日期:——
been developed for the enantioselective synthesis of tetrahydro-1H-pyrrolizin-3(2H)-ones starting from α,β-unsaturated aldehydes via a sequence of asymmetric Michael–oxidative esterification–Michal–reduction–reductive amination–lactamization reactions with high enantioselectivities (93–97% ee). The six-step reaction sequence can be conducted with the pot-economy synthetic strategy with only a one-step