Highly Stereoselective Synthesis of Cyclopropylphosphonates Catalyzed by Chiral Ru(II)-Pheox Complex
摘要:
Ru(II)-Pheox-catalyzed asymmetric cyclopropanation of diethyl diazomethylphosphonate with alkenes, including alpha,beta-unsaturated carbonyl compounds, afforded the corresponding optically active cyclopropylphosphonates in high yields and with excellent diastereoselectivity (up to 99:1) and enantioselectivity (up to 99% ee).
Catalytic asymmetric synthesis of cyclopropylphosphonates Catalysts' scope and reactivity
作者:André B Charette、Jean-Emmanuel Bouchard
DOI:10.1139/v05-074
日期:2005.6.1
The transition metal-catalyzed cyclopropanation of alkenes using α-diazomethylphosphonates leads to cyclopropylphosphonate derivatives in high yields. The reaction proceeds well with copper, rhodium, and ruthenium catalysts. The best catalysts for the enantioselective version are either Evans' Cu·bis(oxazoline) or Nishiyama's Ru·pybox.Key words: cyclopropylphosphonic acids, copper catalysts, ruthenium