Kinetic resolution is a powerful technique to obtain enantioenriched compounds. A major drawback to conventional kinetic resolutions is that the final purification step to isolate the stereoenriched compounds usually employs chromatography, which is costly and difficult to perform on an industrial scale. Recent advances have demonstrated the applicability of polymer supports as a means of separating enantiomerically enriched starting materials from products in kinetic resolutions by having one enantiomer attached to the polymer and the other in solution. Herein, several approaches are reviewed in which either homogenous or heterogeneous macromolecules are employed to facilitate a chromatography-free isolation of stereoenriched compounds. Kinetic resolutions employing enzymatic, transition-metal, or small-molecule-catalyzed reactions by using polymeric materials will be discussed.

A silyl chloride derivatized styrene polymer was employed in the silylation-based kinetic resolution of secondary alcohols for chromatography-free separation of alcohol enantiomers. Synthetically useful selectivity factors were obtained; furthermore, the polymer was recycled for use in a subsequent kinetic resolution, and it maintained its selectivity and integrity.

The impact of the structure and conformation of formamides as organocatalysts was investigated and reported herein as a structure–activity relationship. Selected formamides and some amides were evaluated for their ability to activate allyltrichlorosilane in the allylation of benzaldehyde. The results suggest that the reactive conformation of secondary formamides is the less-favorable cis conformation, whereas tertiary formamides and most amides are less reactive or unreactive in the reaction. A trend is observed between the Charton value for the N-substituent on the secondary formamides and the amount of product formed, with an increase in yield as the substituent becomes larger. This work highlights the effects of sterics and solvent polarity on the reactivity of formamides.