Enantioselective cyanoformylation of aldehydes catalyzed with solid base mediated chiral V(V) salen complexes.
Polymeric and monomeric V(V) chiral salen complexes-catalyzed enantioselective ethyl cyanoformylation of aldehydes using ethyl cyanoformate as a source of cyanide was accomplished in the presence of several basic cocatalysts viz., NaOH, KOH, basic Al2O3 and hydrotalcite. Excellent yield (>95%) of chiral ethyl cyanohydrincarbonate with high enantioselectivity up to 94% was achieved in 24-36 h when hydrotalcite was used as an additive. The polymeric catalyst 1 is more reactive than the monomeric catalyst 2 to produce chiral ethyl cyanohydrincarbonate in high optical purity. The chiral polymeric catalyst 1 and cocatalysts hydrotalcite and basic alumina used in this study were recoverable and recyclable several times with retention of its performance.
Khan
Noor-Ul H
NU
Discipline of Inorganic Materials and Catalysis, Central Salt and Marine Chemicals Research Institute (CSMCRI), Bhavnagar, Gujarat, India. khan2593@yahoo.co.in
Agrawal
Santosh
S
Kureshy
Rukhsana I
RI
Abdi
Sayed H R
SH
Pathak
Kavita
K
Bajaj
Hari C
HC