Polyamino acids as catalysts in asymmetric synthesis
摘要:
The use of polyamino acids in asymmetric organic synthesis is reviewed. Particular emphasis is placed on the asymmetric epoxidation of alpha,beta-unsaturated ketones with hydrogen peroxide in the presence of polyalanine or polyleucine, and further transformations of the epoxide products. (C) 1999 Elsevier Science Ltd. All rights reserved.
Asymmetric epoxidation of enones employing polymeric α-amino acids in non-aqueous media
作者:Paul A. Bentley、Sophie Bergeron、Michael W. Cappi、David E. Hibbs、Michael B. Hursthouse、Thomas C. Nugent、Rosalino Pulido、Stanley M. Roberts、L. Eduardo Wu
DOI:10.1039/a700550d
日期:——
Ureaâhydrogen peroxide complex in an organic solvent and in the
presence of DBU and poly-(L)-leucine causes rapid asymmetric
epoxidation of the enones 1a, b and d.
Poly-L-leucine catalysed epoxidation reactions: A short, stereoselective route to chiral α,β-epoxyalcohols
作者:Adam T. Gillmore、Stanley M. Roberts、Mike B. Hursthouse、K.M. Abdul Malik
DOI:10.1016/s0040-4039(98)00479-1
日期:1998.5
alkylation of epoxyketones (1), (4) from Poly-L-leucine catalysed asymmetric epoxidation of α,β-unsaturated ketones provides a short, stereocontrolled route to optically pure α,β-epoxy tertiary alcohols (2), (3). These epoxyalcohols undergo Payne rearrangement in mild Lewis acid conditions to give the isomeric α,β-epoxy secondary alcohols (5), (6). Alternatively, the epoxide may be opened up in a highly regio-
Polyamino acids as catalysts in asymmetric synthesis
作者:Michael J. Porter、Stanley M. Roberts、John Skidmore
DOI:10.1016/s0968-0896(99)00144-3
日期:1999.10
The use of polyamino acids in asymmetric organic synthesis is reviewed. Particular emphasis is placed on the asymmetric epoxidation of alpha,beta-unsaturated ketones with hydrogen peroxide in the presence of polyalanine or polyleucine, and further transformations of the epoxide products. (C) 1999 Elsevier Science Ltd. All rights reserved.
Synthesis and reactions of some optically active epoxides formally derived from tertiary allylic alcohols
作者:Jamie F. Bickley、Adam T. Gillmore、Stanley M. Roberts、John Skidmore、Alexander Steiner
DOI:10.1039/b008275i
日期:——
The epoxyketones 2, 3 and 7–9 reacted with Grignard reagents in a highly stereocontrolled manner to give the epoxyalcohols 20, 4–6 and 11-13 in high yields. The epoxyalcohol 12 underwent a Payne rearrangement on base treatment to give the isomer 15 while epoxyalcohols 4, 5, 12 and 20 suffered ring-opening (with retention of configuration) using tin(IV) chloride to afford chlorodiols 18, 17, 19 and