Advances in asymmetric oxidative kinetic resolution of racemic secondary alcohols catalyzed by chiral Mn(III) salen complexes

Abstract

Enantiomerically pure secondary alcohols are essential compounds in organic synthesis and are used as chiral auxiliaries and synthetic intermediates in the pharmaceutical, agrochemical, and fine chemical industries. One of the attractive and practical approaches to achieving optically pure secondary alcohols is oxidative kinetic resolution of racemic secondary alcohols using chiral Mn(III) salen complexes. In the last decade, several chiral Mn(III) salen complexes have been reported with excellent enantioselectivity and activity in the homogeneous and heterogeneous catalysis of the oxidative kinetic resolution of racemic secondary alcohols. This review article is an overview of the literature on the recent development of chiral Mn(III) salen complexes for oxidative kinetic resolution of racemic secondary alcohols. The catalytic activity of monomeric, dimeric, macrocyclic, polymeric, and silica/resin supported chiral Mn(III) salen complexes is discussed in detail.

Deracemization of 1-phenylethanols in a one-pot process combining Mn-driven oxidation with enzymatic reduction utilizing a compartmentalization technique

“…9 The eld has been well systematized and much research has been reviewed in this decade. [10][11][12][13][14] Recently, enzymatic oxidation/reduction has become a hot topic as a method to obtain optically pure secondary alcohols from unwanted "waste" enantiomers or inexpensive racemates. [15][16][17] In particular, one-pot tandem reactions combining multiple enzymes have successfully overcome the weaknesses of multi-step synthesis, such as time wastage, isolation work that reduces the yield, and purication of intermediates.…”

Diastereoselective Electrophile‐Directed Alkylations

“…Catalytic advances have been particularly effective in accessing a diverse suite of chiral alcohols that are readily activated to afford chiral electrophiles . The potential of chiral electrophiles lies in using robust enolate/anion methodology ( 1 → 2 ) to simultaneously install two chiral centers, one through a predictable S N 2 displacement and the other through a matched facial attack on the nucleophile (Scheme , 2 + 3 → 4 ).…”

Enhanced Activity and Enantioselectivity of Henry Reaction by the Postsynthetic Reduction Modification for a Chiral Cu(salen)-Based Metal–Organic Framework

“…Recently, MOFs, also known as porous coordination polymers, have drawn considerable attention as very prominent materials for heterogeneous catalysis owing to their high surface areas, adjustable pore volume and shape, tunable composition (organic linkers or metal clusters), and amenability to bottom-up assembly methodology . MOFs having imbedded, well-defined privileged molecular catalysts are of particular interest due to their higher catalytic activities derived from MOFs pore/channel confinement effect, improved lifetime through eliminating the multimolecular deactivation pathways, and recyclability based on their heterogeneity. , Following this synthetic strategy and motivated by the excellent asymmetric catalytic activities of metallosalen compounds, , a number of MOFs constructed by chiral M­(salen)-derived ligands (M: Cu/Ni/​Co/​Fe/​Mn/​Cr/​VO/Ru) were synthesized over the past decade . These M­(salen)-based MOFs were extensively used in various asymmetric catalytic reactions, such as epoxidation of olefins, hydrolytic kinetic resolution, olefin aziridination, cyclopropanation, cyanosilylation, aminolysis of epoxides, and cycloaddition reaction of CO 2 with epoxides .…”