Daniel Méndez-Sánchez

Chemoenzymatic Deracemization of Secondary Alcohols by using a TEMPO–Iodine–Alcohol Dehydrogenase System

A deracemization system for secondary alcohols was established after the analysis of individual steps and their compatibility in one pot. The chemical oxidation and bioreduction occurred in a sequential manner to yield 1‐arylethanols and lineal aliphatic alcohols with excellent conversions and enantiomeric excess values. The oxidation step was performed by using 2,2,6,6‐tetramethylpiperidin‐1‐oxyl and iodine. This chemical process was extremely favored by sonication, which allowed quantitative formation of the corresponding ketone intermediates after just 1 h. Simple destruction of iodine in the same pot allowed sequential bioreduction of the ketones by using either Prelog or antiPrelog enzymes, which led to the preparation of the enantiopure alcohols in excellent yields.