Combined computational and experimental investigations on the diastereoselective hydrogenation of steroids by chiral oxazaborolidine

Göndös, Gy. and Pálinkó, István (2001) Combined computational and experimental investigations on the diastereoselective hydrogenation of steroids by chiral oxazaborolidine. INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, 84 (2). pp. 253-258. ISSN 0020-7608

Text 1143707.pdf Restricted to Registered users only Download (135kB) | Request a copy

Abstract

In this work the results of semiempirical quantum chemical calculations are described that support experimental findings applying the methyl derivative of oxazaborolidine-BH3 chiral complex for the reduction of a number of pregnane derivatives (3 alpha -hydroxy-5 beta -pregnane-20-one, 3 alpha ,17 alpha -dihydroxy-5 beta -pregnane-20-one, 3 alpha ,21-dihydroxy-5 beta -pregnane-20-one, and 3 alpha ,17 alpha ,21-trihydroxy-5 beta -pregnane-20-one). Calculations were performed by the MNDO method. The reactants, the products, the assumed transition states, as well as the assumed intermediate structures were optimized without any constraints. Calculations were able to reproduce the observed activity sequence and explain the experimental finding that the thermodynamically less stable isomer is formed preferentially.

Actions (login required)

Edit Item