A new chiral catalyst for olefin metathesis is prepared from commercially available materials and is equally or more effective and selective than the previous systems. The new user-friendly catalyst can be prepared in situ (see scheme, Ar=aryl, Tf=trifluoromethanesulfonyl), isolation not needed, outside of a glove box, and delivers reactivity and enantioselectivity levels formerly available only through
Mechanistically Inspired Catalysts for Enantioselective Desymmetrizations by Olefin Metathesis
作者:Pierre-André Fournier、Jolaine Savoie、Brice Stenne、Marion Bédard、Alain Grandbois、Shawn K. Collins
DOI:10.1002/chem.200800642
日期:2008.9.26
In asymmetric olefin metathesis reactions, the addition of halideadditives is often required to augment enantioselectivities, despite the fact that the additives result in catalysts with diminished reactivities. The preparation of new chiral Ru-based catalysts was accomplished by exploiting previously reported mechanistic studies. The catalysts possess a high level of reactivity and successfully induce