Recent Advances in Asymmetric Organomulticatalysis

Abstract

Asymmetric multi‐catalysis, designed to mimic catalytic processes in nature, is a powerful instrument to fulfil fascinating transformations. As a result, this area of research has attracted considerable interests within chemistry communities. Although there are numerous reviews involving multi‐catalysis, reviews describing asymmetric organomulticatalysis remain rare. Taking into consideration that organocatalysts possess the superiorities of effortless availability, inexpensiveness, hypotoxicity, facile handling and hyposensitivity to moisture and oxygen, they have definite advantage in their own distinct modes of activation when utilized in multi‐catalytic reactions. Organomulticatalysis refers to the synthetic strategies of modular combination of organo‐catalyzed reactions into one synthetic operation with minimum workup or change in conditions. It is apparent that a variety reports utilizing the concept of enantioselective organomulticatalysis have substantially surfaced in the past few years. Hence, it is indispensable to succinctly present all such reports by means of disclosing the mechanistic analysis, as well as the challenges and issues associated in the development of the asymmetric catalytic system. Additionally, this review will introduce some of the unsettled conundrums and possible innovations in this field.

Robust, scalable construction of an electrophilic deuterated methylthiolating reagent: facile access to SCD3-containing scaffolds

“…According to the previous studies, S -alkyl(aryl) thiosulfonates were the excellent reagents to realize a series of exquisite transformations and late-stage modifications. 18 Inspired by the sulfur atom transfer (SAT) strategy, 19 we expect to utilize an odourless thiosulfonate salt to fulfil the formation of a versatile S -methyl- d 3 reagent. Recently, Wang et al disclosed a novel process to synthesize an excellent liquid S -methyl- d 3 reagent (PhSO 2 SCD 3 ) from DMSO- d 6 with two steps, in which a large amount of DMSO- d 6 was essential, and the yield of deuterated reagent was not reported (Fig.…”

“…The 1,3-dicarbonyl compounds smoothly reacted with TsSCD 3 to furnish the desired products bearing a quaternary carbon center ( 7a–7c ). The chiral amine catalysis 19 k was also investigated and led to forming the chiral product 7b in a high yield with moderate enantioselectivity (for details, please see the Page 6 of ESI†). Trideuteromethylthioester could be efficiently generated from aldehydes with the help of tert -butylhydroperoxide (TBHP) via an intermolecular radical process ( 7d-e ).…”

Asymmetric organocatalyzed synthesis of coumarin derivatives

“…The use of multicatalytic systems have become a useful strategy for the case where it is not possible to achieve the desired transformation by using only one catalyst [ 70 ]. In this sense, an efficient asymmetric organocatalytic reaction was reported by Zhang et al for the synthesis of 2,8-dioxabicyclo[3.3.1]nonanes [ 71 ].…”

Further developments of β,γ-unsaturated α-ketoesters as versatile synthons in asymmetric catalysis

“…Rapid preparation of complex structures from readily accessible starting materials with multiple reaction modes in a catalytic asymmetric manner is one of the central themes in synthetic chemistry. The resulting chiral molecules with structural complexity and diversity are not only important synthons in organic synthesis, but also of great significance and value for hit-to-lead optimization efforts in medicinal chemistry ( Kim and Li, 2020 ; Mei et al., 2021 ; Xiao et al., 2020 ). In this context, β,γ -unsaturated α -ketoesters are a class of privileged unsaturated carbonyl derivatives, because of their unique 1,2-dicarbonyl system.…”