Directing Group‐Promoted Inert C−O Bond Activation Using Versatile Boronic Acid as a Coupling Agent
作者:Ram Ambre、Ting‐Hsuan Wang、Anmei Xian、Yu‐Shiuan Chen、Yu‐Fu Liang、Titel Jurca、Lili Zhao、Tiow‐Gan Ong
DOI:10.1002/chem.202004132
日期:2020.12.18
strategy facilitates the efficient catalytic cross‐coupling of methoxyarenes with a variety of organoboronreagents. Directing groups facilitate the activation of inert C−O bonds in under‐utilized aryl methyl ethers enabling their adaptation for C−C cross‐coupling reactions as less toxic surrogates to the ubiquitous haloarenes. The method reported enables C−C cross‐coupling with readily available and economical
Copper-Mediated Chelation-Assisted <i>Ortho</i> Nitration of (Hetero)arenes
作者:Lin Zhang、Zhenhua Liu、Huiqin Li、Guichun Fang、Badru-Deen Barry、Tuemay Abadi Belay、Xihe Bi、Qun Liu
DOI:10.1021/ol2028288
日期:2011.12.16
A novel copper-mediated chelation-assisted ortho C–H nitration of (hetero)arenes has been developed for the first time, which used dioxygen as terminal oxidant and 1,2,3-TCP as solvent, leading to the synthesis of nitroaromatics with excellent regioselectivity and in good yields. Mechanistic investigations indicate a mechanism involving a four-centered transition state, with simultaneous cleavage of
<i>S</i>-Aryl Arenesulfonothioate and Copper Acetate Mediated Arylthiolation of 2-Arylpyridines and Heteroarenes
作者:Poonam Sharma、Nidhi Jain
DOI:10.1021/acs.joc.9b01954
日期:2019.10.18
Copperacetate mediated regioselective ortho-arylthiolation of 2-arylpyridines has been accomplished for the first time using S-aryl arenesulfonothioate as the arylthiolating agent. The reaction shows good functional group tolerance and gives thioarylated products in 67-89% yields. This reagent is a good alternative to unpleasant smelling arylthiols. Experimental evidence suggests an unprecedented
Copper-catalysed regioselective azidation of arenes by C–H activation directed by pyridine
作者:Chandra S. Azad、Anudeep K. Narula
DOI:10.1039/c5ra21963a
日期:——
A novel and efficient copper-catalysed pyridine directed ortho-azidation of arenes has been developed using safe and stable benzotriazole sulphonyl azide as the azidating agent.
Reductive cleavage of aromatic and benzylic C–O bonds by chromium catalysis is reported. This deoxygenative reaction was promoted by low-cost CrCl2 precatalyst combined with poly(methyl hydrogen siloxane) as the mild reducing agent, providing a strategy in forming reduced motifs by cleavage of unactivated C–O bonds. A range of functional groups such as bromide, chloride, fluoride, hydroxyl, amino,