Force field parameters for the boronate function and their carbonyl complexes and application to modelling boronate esters

MM2 force field parameters have been developed for alkyl- and aryl-boronates and for their carbonyl Lewis-acid complexes, from a combination of X-ray crystallographic data, infrared spectroscopy, ab initio and semi-empirical calculations. The resulting parameters, when used in conjunction with MacroModel, reproduce the geometry of ab initio and MNDO calculated and X-ray crystal structures with high accuracy, and have been used to model chiral boronate esters to explain the origin of stereoselective reduction reactions of boronate complexes 3 and 4.