A new asymmetric synthesis of 2,6-cis-disubstituted 4-methylenepiperidines: total synthesis of (+)-alkaloid 241D and (+)-isosolenopsin A
摘要:
A highly diastereoselective synthesis of 2,6-cis-disubstituted-4-methylenepiperidines based on a Mannich type intramolecular cyclization of an allylsilane on an iminium ion is described. The synthetic potential of this methodology is demonstrated by the enantioselective synthesis of two natural piperidine alkaloids: (+)-alkaloid 241 D and (+)-isosolenopsin A. (C) 2005 Elsevier Ltd. All rights reserved.
The synthesis of chiral (2-substituted-2-aminoethyl)allylsilanes by cerium mediated trimethylsilylmethylmagnesium chloride addition to the ester group of non racemic chiral β-aminoesters is described.
A highly diastereoselective synthesis of 2,6-cis-disubstituted-4-methylenepiperidines based on a Mannich type intramolecular cyclization of an allylsilane on an iminium ion is described. The synthetic potential of this methodology is demonstrated by the enantioselective synthesis of two natural piperidine alkaloids: (+)-alkaloid 241 D and (+)-isosolenopsin A. (C) 2005 Elsevier Ltd. All rights reserved.