A Computational Mechanistic Study of the Chemo‐ and Enantioselectivity in the 1,4‐Addition Reaction Catalyzed by a Rh Complex of Sulfinyl‐Phosphine.

Computational modelling provides a powerful tool for predicting the possibility of a reaction and permits an important quantitative evaluation of the chemo‐ and enantioselectivities in reactions. Here we present the results of DFT calculations of the chemo‐ and enantioselectivities of the 1,4‐addition of phenylboronic acid to β,γ‐unsaturated α‐ketoamides or α‐ketoesters catalyzed by Rh ligated to a sulfinyl‐phosphine ligand. For the three substrates studied, the predicted chemoselectivity and absolute configuration agree with experimental observations. The ee values calculated at the SMD/M06/DGDZVP level of theory were more accurate than those determined by the IEFPCM/PBE0/DGDZVP method. The high steric pressure exercised by the tBu and diphenylphosphine groups are the origin of the chemo‐ and enantioselectivities of the 1,4‐addition reactions. [ABSTRACT FROM AUTHOR]