<i>ortho</i>‐Allylation of 2‐Arylindazoles with Vinyl Cyclic Carbonate and Diallyl Carbonate <i>via</i> Manganese‐Catalyzed C−H Bond Activation

Pyne

et al. 2022

The Chemical Record

Self Cite

C−H Functionalization is ubiquitously considered as a powerful, efficient and handy tool for installing various functional groups in complex organic heterocycles in an easier and step‐economic way. Similarly, indazole is endowed as a potent heterocycle and is eminent for its profound impact in biological, medicinal and industrial chemistry. In this scenario, C−H functionalization at the selective ortho position of 2‐arylindazole in assistance of a metal catalyst is also becoming an appealing approach in synthetic organic chemistry. This review addressed the recent findings and developments on ortho C−H functionalization of 2‐aryl‐2H‐indazazoles with literature coverage extending from 2018 to May 2022.

Section: Allylationmentioning

confidence: 99%

OrthoC−H Functionalizations of 2‐Aryl‐2H‐Indazoles

Pyne

et al. 2022

The Chemical Record

Self Cite

Recent Advances and Prospects in Manganese‐Catalyzed C−H Activation

Anusree,

Devi,

Anilkumar

2024

Adv Synth Catal

C–H activation represents an interesting alternative to conventional cross‐coupling methods, avoiding the requirement of additional steps to introduce activating groups. Generally, Pd‐catalyzed reactions have been extensively employed for C–H activation. The high cost and limited availability of resources of Pd have prompted us to explore alternative transition metals. In this context, researchers are turning to Earth Abundant Metals (EAMs) like manganese and iron for their potential in C–H activation.Significant progress has been made in manganese‐catalyzed C–H activation in recent years, showcasing excellent specificity, environmental compatibility, and versatility across different substrates. This review summarizes approximately 50 recent publications highlighting significant advancements in this field from 2020 to 2023.

Chemistry An Asian Journal

Manganese‐Catalyzed C(sp²)−H Alkylation of Indolines and Arenes with Unactivated Alkyl Bromides

Verma

Punji

2022

Selective C(sp2)−H bond alkylation of indoline, carbazole and (2‐pyridinyl)arenes with unactivated alkyl bromides is achieved using MnBr2 catalyst in the absence of an external ligand. The alkylation uses a simple LiHMDS base and avoids the necessity of Grignard reagent, unlike other Mn‐catalyzed C−H functionalization. This reaction proceeded either through a five‐ or a less‐favored six‐membered metallacycle, and tolerated diverse functionalities, including alkenyl, alkynyl, silyl, aryl ether, pyrrolyl, indolyl, carbazolyl and alkyl bearing fatty alcohol and polycyclic‐steroid moieties. Alkylation follows a single electron transfer (SET) pathway involving 1e oxidative addition of alkyl bromide and a rate‐limiting C−H metalation.