B. Alcaide, P. Almendros, A. Luna
Jan 16, 2008
Citations
0
Influential Citations
16
Citations
Journal
The Journal of organic chemistry
Abstract
Two different stereocontrolled accesses to new 4-hydroxypipecolic acid analogues with a bicyclic beta-lactam structure have been developed by using intramolecular reductive amination or allenic hydroamination reactions in 2-azetidinone-tethered azides. The access to the cyclization precursors was achieved from 3-azido-4-oxoazetidine-2-carbaldehyde via metal-mediated carbonyl-allenylation in aqueous environment or by organocatalytic direct aldol reaction. The tin hydride-promoted cyclization of the 2-azetidinone-tethered azidoallene is totally regioselective for the central allenic carbon providing a fused piperidine.