Enantio- and diastereoselective Darzens condensations
作者:Thierry J.R. Achard、Yuri N. Belokon’、Michael Ilyin、Margarita Moskalenko、Michael North、Francesca Pizzato
DOI:10.1016/j.tetlet.2007.03.009
日期:2007.4
A cobalt(salen) complex has been shown to catalyse the asymmetric Darzenscondensation between α-haloamides and aldehydes, allowing both the relative and absolute stereochemistry of the epoxy-amide products to be controlled. Under optimal conditions, cis-epoxides can be obtained diastereoselectively with up to 50% enantiomeric excess, whilst by changing the leaving group and base, trans-epoxides can