The Different Facets of Metal‐Catalyzed C−H Functionalization Involving Quinone Compounds

Abstract

Metal‐catalysed C−H functionalization has emerged as a powerful platform for the derivatization of quinones, a class of compounds with wide‐ranging applications. This review organises and discusses the evolution of this chemistry from early Fujiwara‐Moritani reactions, through to modern directing‐group assisted C−H functionalization processes, including C−H functionalization reactions directed by the quinone ring itself. Mechanistic details of these reactions are provided to afford insight into how the unique reactivity of quinoidal compounds has been leveraged in each example.

Synthesis of spiropyrans via Ru(ii)-catalyzed coupling of 3-aryl-2H-benzo[b][1,4]oxazines with benzoquinones

“…Benzoquinone, an easily accessible synthon, has been successfully used as a coupling partner for the direct construction of several hard-to-prepare cyclic skeletons via transitionmetal catalyzed C-H activation, as reported by the groups of Xu, Wang, Fan and others. 9 In continuation of our interest in the synthesis of spiropyrans with 3-aryl-2H-benzo [b][1,4]oxazines, we reasoned that benzoquinone may be used as a C 3 synthon to afford the target molecules. To achieve this goal, the following challenges have to be overcome (Scheme 1b):…”

Annulations involving p-benzoquinones: stereoselective synthesis of fused, spiro and bridged molecules

“…54 Recently, two review articles have been published mainly highlighting metal-catalyzed strategies for the C-H functionalization of benzoquinones. 55,56 However, last few years have witnessed a remarkable progress in stereo-controlled reactions involving p-benzoquinones, and thus a new direction on this topic seems appropriate. The present review surveys the recent progress (2018-2023) in annulation reactions involving p-benzoquinones towards the stereoselective formation of fused, spiro and bridged/cage molecular scaffolds.…”

Silver-catalyzed cascade cyclization and functionalization of N-aryl-4-pentenamides: an efficient route to γ-lactam-substituted quinone derivatives

“… 2 Consequently, the development of general and efficient methodologies to incorporate functional groups into 1,4-naphthoquinones is of great importance. 3 However, common strategies that would allow access to such compounds suffer from several drawbacks. The prevailing transition-metal-catalyzed method usually works sluggishly due to the ability of quinone substrates to act as ligands and oxidants, 4 even workable examples of these underwent a Kochi–Anderson type reaction, 5 despite a few exceptions.…”