Oxovanadium(v)-catalyzed oxidative cross-coupling of enolates using O₂ as a terminal oxidant

Abstract

The oxovanadium(v)-catalyzed oxidative cross-coupling of enolates using O2 as a terminal oxidant is reported, where a boron enolate and a silyl enol ether were employed as enolates.

Transformations of Main-Group Organometallics Induced by Transition Metals

“…Furthermore, the reaction proceeds catalytically under molecular oxygen (Scheme 16). 24 The choice as radical generator or acceptor is controlled by their redox potentials as mentioned above. The above-mentioned coupling reaction of main-group organometallic compounds provides versatile methods for carbon-carbon bond formation of nucleophiles, which is a complementary strategy of common nucleophile-electrophile coupling reactions.…”

Recent Advances in the Oxidative Coupling Reaction of Enol Derivatives

“…图式 24 硼烯醇化合物交叉氧化偶联反应 Scheme 24 Oxidative cross-coupling of boron enolate reported by Hirao's group 2020 年, 他们 [51] 更是利用催化量的钒盐作单电子 氧化剂来实现上述化学转化, 并采用电子自旋共振谱法 (ESR)和 51 V NNR 技术研究了钒的变化(Scheme 25). [19] .…”

Enantioselective Oxidative Enolate Coupling of Oxindoles Catalyzed by Chiral Guanidinium Hypoiodite

“…Bond-forming umpolung reactions at the α-position in carbonyl groups have been well investigated, as exemplified by the well-known construction of 1,4-dicarbonyl compounds via the catalytic coupling reaction of two carbonyl enolates under oxidative conditions. − Asymmetric versions of this reaction are particularly desirable, and so far, two types of strategies have emerged for highly enantioselective catalytic asymmetric enolate coupling reaction: (i) utilizing a stoichiometric amount of a metal-based or organic oxidant, such as DDQ and CAN, in the presence of a chiral catalyst, − and (ii) electrochemical oxidation in the presence of a chiral Lewis acid . However, in the cross-coupling reaction of two different enolates, one of the enolates should be selectively prefunctionalized to avoid the generation of homotype coupling products (Figure a). ,− …”