Asymmetric synthesis of 3- or 4-alkyl or arylbenzo[c]azepines
摘要:
Two flexible routes for the stereoselective synthesis of a variety of 3- or 4-alkylated or arylated tetra-hydrobenzazepines have been developed. The key steps are the highly diastereoselective metallation/alkylation reaction and 1,2-addition processes applied to stereopure SAMP hydrazones combined with a cyclomethylenation reaction. (C) 2009 Elsevier Ltd. All rights reserved.
A concise asymmetricsynthesis of chiral bicyclic lactams combining a highly stereoselective 1,2-addition on SAMPhydrazones with a ring closure metathesis has been achieved. The synthetic utility of this approach has been emphasized by the totalsynthesis of (-)-coniceine in high enantiomeric excess.