Metal‐Catalyzed β‐Functionalization of Michael Acceptors through Reductive Radical Addition Reactions

Abstract

Transition-metal-catalyzed radical reactions are becoming increasingly important in modern organic chemistry. They offer fascinating and unconventional ways for connecting molecular fragments that are often complementary to traditional methods. In particular, reductive radical additions to α,β-unsaturated compounds have recently gained substantial attention as a result of their broad applicability in organic synthesis. This Minireview critically discusses the recent landmark achievements in this field in context with earlier reports that laid the foundation for today's developments.

Mn-, Fe-, and Co-Catalyzed Radical Hydrofunctionalizations of Olefins

“…Post 2014, this MH HAT hypothesis was suddenly and widely adapted in research articles and literature reviews to characterize the field. 5,6,7,24,27,397 …”

“…Retrospective application of a MH HAT mechanism to net redox-neutral catalytic transformations would resemble a cycle like that in Figure 164, 28 variants of which have now appeared in literature reviews. 5,6,7 Such metal hydride reactivity is based on mechanistic investigations that began in the latter half of the last century.…”

Merging Regiodivergent Catalysis with Atom‐Economical Radical Arylation

“…[2] Herein, we show the validity of these points in at itanocene-catalyzed [3] regiodivergent radical arylation that allows access to enantiomerically pure tetrahydroquinolines or indolines from ac ommon starting material through choice of the appropriate titanocene catalyst. The regioselectivity of epoxideo pening that results in the high selectivity of heterocycle formation is controlled by two factors,t he absolute configuration of the enantiopure ligands of the (C 5 H 4 R) 2 TiX 2 catalyst and the inorganic ligand X( X = Cl, OTs).…”

Nickel-Catalyzed Reductive Conjugate Addition of Primary Alkyl Bromides to Enones To Form Silyl Enol Ethers

“…We report herein a new ligand–catalyst combination that solves this challenge and provides high yields of silyl enol ether product with primary alkyl bromides. 7−9 …”