Cooperative dual catalysis: application to the highly enantioselective conjugate cyanation of unsaturated imides.
Cooperative heterobimetallic catalysis was used as a design principle to achieve a highly reactive system for the enantioselective conjugate addition of cyanide to alpha,beta-unsaturated imides. A dual-catalyst pathway involving chiral (salen)Al complex 1b and chiral (pybox)Er complex 4b provides measurable improvements in rates and enantioselectivities relative to single-catalyst systems. Mechanistic studies point to a cooperative bimetallic mechanism involving activation of the imide by the Al complex and activation of cyanide by the Er complex.
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA.
Glenn M
GM
Sammis
Hiroshi
H
Danjo
Eric N
EN
Jacobsen
D000077410:Aluminum Chloride; D017607:Aluminum Compounds / Q000737:chemistry; D002384:Catalysis; D002712:Chlorides / Q000737:chemistry; D005029:Ethylenediamines / Q000737:chemistry; D006856:Hydrogen Cyanide / Q000737:chemistry*; D007094:Imides / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry; D009942:Organometallic Compounds / Q000737:chemistry*; D013237:Stereoisomerism
D017607:Aluminum Compounds; D002712:Chlorides; D005029:Ethylenediamines; D007094:Imides; D028581:Lanthanoid Series Elements; D009942:Organometallic Compounds; D006856:Hydrogen Cyanide; D000077410:Aluminum Chloride; C011452:disalicylaldehyde ethylenediamine