Combining Q2MM modeling and kinetic studies for refinement of the osmium-catalyzed asymmetric dihydroxylation (AD) mnemonic

The interactions between the substrate and the ligand in the Sharpless AD reaction have been examined in detail, using a combination of substrate competition experiments and molecular modeling of transition states. There is a good agreement between computational and experimental results, in particular for the stereo selectivity of the reaction. The influence of each moiety in the second-generation ligand (DHQD)(2)PHAL on the rate and selectivity of the reaction has been elucidated in detail. (c) 2005 Elsevier B.V. All rights reserved.