1,3-Dipolar Cycloadditions of Carbonyl Ylides to Aldimines: Scope, Limitations and Asymmetric Cycloadditions
作者:Staffan Torssell、Peter Somfai
DOI:10.1002/adsc.200600324
日期:2006.11
The development of a diastereoselective 1,3-dipolarcycloaddition of carbonylylides and imines for the synthesis of α-hydroxy-β-amino esters is described. The methodology is successfully applied to chiral α-methylbenzylimines affording enantiomerically pure syn-β-amino alcohols, which is exemplified with a short asymmetric synthesis of the paclitaxel side-chain. The use of chiral Rh(II) carboxylate
Addition of titanium ester enolates to N-arylidene derivatives containing a (R)-alpha-methylbenzylamine moiety afforded (2S,3S,alpha R)-beta-amino esters in 73-93% yields with 86:14 to 96:4 diastereomeric ratios. (c) 2006 Elsevier Ltd. All rights reserved.