Photoinduced Deracemization of [Co(acac)_3] (acac~-=acetylacetonate) with Chiral #DELTA#-[Ru(menbpy)_3]~(2+) (menbpy=4,4'-bis{(1R,2S,5R)-(-)-menthoxycarbonyl}-2,2'-bipyridine)

摘要

Deracemization of a racemic mixture of #DELTA#- #LAMBDA#-[Co(acac)_3] (acac~-=acetylacetonate) was successfully carried out with a chiral ruthenium(II) complex, #DELTA#-[Ru(menbyp)_3]~(2+) [menbpy = 4,4'-bis (1R,2S,5R)-(-)-menthoxycarbonyl}-2,2'-bipyridine], in acetnitrile-H_2O (7:3 v/v), in the presence of either triethylamine or NaOH under bisible light irradiation (420 <#gamma#<470 nm). The #LAMBDA#-isomer was obtained preferentially with the enantiomeric excess of 38%.