Add time:08/11/2019         Source:sciencedirect.com

Catalytic Meerwein–Ponndorf–Verley (MPV) reduction using AlIII–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.

We also recommend Trading Suppliers and Manufacturers of 4-TERT-BUTYL-4'-FLUOROBENZOPHENONE (cas 16574-58-6). Pls Click Website Link as below: cas 16574-58-6 suppliers