Advances in Chemocatalytic Asymmetric Baeyer–Villiger Oxidations

Abstract

Baeyer–Villiger oxidations, first reported by Adolf von Baeyer and Victor Villiger 120 years ago, are highly efficient methodologies for the syntheses of esters or lactones from ketones. The asymmetric Baeyer–Villiger oxidations using racemic, prochiral and meso‐cyclic ketones allow a rapid access to chiral lactones, which are valuable intermediates for the subsequent synthesis of bioactive compounds and natural products. The current review provides a summary on the advances in chemocatalytic enantioselective B‐V oxidations. The latest achievements in this field and their applications are presented.

Desymmetrization of Prochiral Cyclobutanones via Nitrogen Insertion: A Concise Route to Chiral γ‐Lactams

“…[16] Under the optimized conditions (see SI for further information), high yield was achieved on small as well as gram-scale (Table 1, entries 1a nd 2). Considering the distance of the stereocenters,t he diastereomeric ratio (dr) of 80:20 was quite pleasing, especially since both isomers were easily separable by column chromatography.C hanging the solvent as well as decreasing the temperature led to incomplete conversions and/or the formation of side-products (Table 1, entries [3][4][5][6]. While some solvents (e.g.…”

“…[2] An archetypal example is the Baeyer-Villiger oxidation, which has found numerous applications for the synthesis of chiral g-lactones under remarkably mild condi-tions (Scheme 1a,t op). [3,4] Ther elated asymmetric nitrogenbased ring expansion, which leads to chiral g-lactams, represents an underexplored obstacle,despite the significance of this motif in drug discovery. [5,6] To date,many approved and investigational drugs such as brivaracetam, [7] rolipram, [8] or carmegliptin [9] contain b-substituted g-lactams providing further incentive for the development of such ring-expansions (Scheme 1a,b ottom).…”

Enzymatic Kinetic Resolution by Addition of Oxygen

“…Thef lavin-dependent Baeyer-Villiger monooxygenase (BVMO) catalyses the oxidation of both cyclic and acyclic ketones to lactones and esters,r espectively. [18] Tr aditional chemical methods to achieve the Baeyer-Villiger (BV) transformation [19] typically employ stoichiometric oxidants containing the peroxy linkage;s uch reagents are often heatand shock-sensitive,toxic, and expensive,all of which severely constrain their large-scale industrial application. [20] BVMOs harness aerial molecular oxygen to produce the reactive oxidant in situ at low concentration, offering as afer,g reen alternative with considerable effort now being made to expand the traditionally limited substrate scope of these enzymes and to improve selectivity.…”

Immobilization of Baeyer–Villiger monooxygenase from acetone grown Fusarium sp.

“…Moreover, the stoichiometric amounts of hazardous reagent, a peroxyacid, is converted to a carboxylic acid, producing chemical waste. Therefore, an effort to use environmentally benign oxidants such as H2O2 and O2 has been made (Bryliakov 2017;Liu et al 2020). On the other hand, biocatalysts have been considered to be sustainable catalysts (Matsuda 2017;Dong et al 2018;Sheldon and Woodley 2018;Birolli et al 2019;Wu et al 2020;Koesoema et al 2020).…”