A new approach for the stereoselective synthesis of the piperidine alkaloid (+)-beta-conhydrine based upon a highly diastereoselective 1,2-nucleophilic addition reaction onto a diastereopure hydrazone and ring-closing metathesis as the key steps has been developed. (C) 2008 Elsevier Ltd. All rights reserved.
Diastereoselective construction of syn-α-oxyamines via three-component α-oxyaldehyde–dibenzylamine–alkyne coupling reaction: application in the synthesis of (+)-β-conhydrine and its analogues
variation allows construction of piperidine and pyrrolidine rings while a variation of side arm functionality is achieved by complete regioselective opening of epoxide by different organocopper ylides (Gilman reagents). A lactam–Cu(I) complexation motif is proposed which allows an intramolecular attack of ylides at the terminal epoxy carbon via the six-membered cyclic transition state. The present work