1351162-05-4Relevant articles and documents
MPV reduction using AlIII-calix[4]arene Lewis acid catalysts: Molecular-level insight into effect of ketone binding
Nandi, Partha,Matvieiev, Yuriy I.,Boyko, Vyacheslav I.,Durkin, Kathleen A.,Kalchenko, Vitaly I.,Katz, Alexander
, p. 42 - 49 (2011)
Catalytic Meerwein-Ponndorf-Verley (MPV) reduction using Al III-calix[4]arene complexes is investigated as a model system that requires the bringing together of two different chemical species, ketone and alkoxide, within a six-membered transition state. Two-point versus one-point ketone binding is demonstrated to be the most salient feature that controls MPV catalysis rate. A 7.7-fold increase in rate is observed when comparing reactants consisting of a bidentate Cl-containing ketone and sterically and electronically similar but looser-binding ketones, which are substituted with H and F. The one-point and two-point nature of ketone binding for the various ketones investigated is independently assessed using a combination of structural data derived from single-crystal X-ray diffraction and DFT-based molecular modeling. Using MPV catalysis with inherently chiral calix[4]arenes, the effect of multiple point reactant binding on enantioselectivity is elucidated. A higher denticity of ketone binding appears to increase the sensitivity of the interplay between chiral active site structure and MPV reduction enantioselectivity.
