Diastereo- and enantioselective syntheses of (-)-coniine, (-)-solenopsin A, (-)-solenopsis fugax venom and (-)-xenovenine via deoxygenative decarboxylation of 2-carbonylsultam-substituted N-hydroxy-piperidines and -pyrrolidines

Article abstract of DOI:10.1016/0040-4039(94)88213-4

Heating cyclic 2-carbonylsultam-substituted N-hydroxylamines 4 with NaH yields sultam auxiliary 8 and imines 10, which are trapped in situ either by i-Bu₂AlH or organocerium reagents to give enantiomerically pure 2-mono- or trans-2,6(2,5)-disubstituted piperidines (pyrrolidines) 11 or 12.