Kinetic resolution using enantioimpure catalysts: Mechanistic considerations of complex rate laws

Kinetic resolutions in which the reactions exhibit complex rate laws are discussed. When enantioimpure catalysts are employed, a conversion-dependent selectivity factor k(rel) may in some cases be observed due to "kinetic partitioning" of catalysts within a reaction network. Both asymmetric amplifications and depletions may be observed, and the effects are separate from-and may in some cases be superimposed on-the classic nonlinear effect due to catalyst interactions as those predicted by Kagan's MLn models. Consideration of the conversion dependence of the selectivity factor using enantioimpure catalysts reveals significant detail about the reaction mechanism for the enantiopure case and may offer insights for practical application of kinetic resolution. Examples from the literature are analyzed in the context of kinetic partitioning.