A novel type of catalysts for the asymmetric C-C bond formation based on chiral stereochemically inert cationic Co-III complexes

作者：Belokon Yu N^*; Larionov V A; Mkrtchyan A F; Khrustalev V N; Nijland A; Saghyan A S; Godovikov I A; Peregudov A S; Babievsky K K; Ikonnikov N S; Maleev V I

来源：Russian Chemical Bulletin, 2012, 61(12): 2252-2260.

DOI：10.1007/s11172-012-0320-2

• asymmetric catalysis
• metal complex catalysis
• reaction of the trimethylsilyl-cyanation of aldehydes

Schiff bases derived from (1R,2R)-1,2-diaminocyclohexane and 1 eq. of salycylic (or substituted salycylic) aldehyde form stereochemically inert positively charged chiral octahedral Co (iii) complexes of Delta-configuration with the stereoselectivity approaching 100%. To evaluate the calatylic activity and stereoinduction of the resulting complexes with various counteranions in the outer sphere, a model reaction of trimethylsilyl cyanide addition to benzaldehyde was used. O-trimethylsilylmandelonitrile formed in the process had an enantiomeric purity up to 27%. Complexes with F- counterion showed high catalytic activity.

• 出版日期2012-12