Abstract
<jats:p>Over the past two decades, a variety of protocols involving an enzyme and a transition‐metal‐based racemization catalyst have been developed for the dynamic kinetic resolution (DKR) of secondary alcohols. Several lipases and subtilisin have been employed as the enzyme, and the racemization catalyst is typically a rhodium, ruthenium, vanadium, or aluminum complex. Many structurally diverse racemic secondary alcohols have been effectively “deracemized” by this sequential racemization/selective enzymatic acylation approach. A review of these developments is provided with numerous examples organized by the secondary alcohol structure. Mechanisms for the transition‐metal‐based racemization step are presented for each DKR, as are enantioselectivities for the enzymatic transformations. The chemoenzymatic DKR of a secondary alcohol serves as a key step in the syntheses of several bioactive molecules and enantioenriched polymers, and a selection of these syntheses is presented. The chemoenzymatic DKR of secondary alcohols is compared with other methods such as the analogous enzymatic kinetic resolution, the asymmetric hydrogenation of ketones, and the stereocontrolled nucleophilic addition to aldehydes. Experimental conditions are discussed along with considerations for choosing the optimal enzyme, metal catalyst, and acyl donor. Experimental procedures for the dynamic kinetic resolutions of 16 different secondary alcohols are provided.</jats:p>