Copper porphyrin-catalyzed C(sp2)—O bond construction via coupling phenols with formamides
Copper porphyrin-catalyzed construction of C(sp2)—O bond via coupling formamides with phenols was achieved firstly. A broad range of substrates afforded various carbamates in moderate to good yields with good functional group tolerance at low catalyst loading. Intermolecular competing kinetic isotope effect experiment indicated that the generation of formamide radical is the rate-determining step of current cross-dehydrogenative coupling (CDC) reaction. The research extends the application of metalloporphyrin in CDC reaction.
Pd(II) catalyzed ortho C-H iodination of phenylcarbamates at room temperature using cyclic hypervalent iodine reagents
A novel approach to access ortho iodinated phenols using cyclic hypervalent iodine reagents through palladium(II) catalyzed C-H activation has been developed through weak coordination. The reaction showed excellent regioselectivity, reactivity and good functional group tolerance. A unique mechanism was proposed.
Sun, Xiuyun,Yao, Xia,Zhang, Chao,Rao, Yu
supporting information
p. 10014 - 10017
(2015/06/22)
Room-temperature Pd-catalyzed C-H chlorination by weak coordination: One-pot synthesis of 2-chlorophenols with excellent regioselectivity
A room-temperature Pd(ii)-catalyzed regioselective chlorination reaction has been developed for a facile one-pot synthesis of a broad range of 2-chlorophenols. The reaction demonstrates an excellent regioselectivity and reactivity for C-H chlorination. This reaction represents one of the rare examples of mild C-H functionalization at ambient temperature.
Sun, Xiuyun,Sun, Yonghui,Zhang, Chao,Rao, Yu
supporting information
p. 1262 - 1264
(2014/02/14)
A general approach towards catechol and pyrogallol through ruthenium- and palladium-catalyzed C-H hydroxylation by weak coordination
An efficient ruthenium(II)- and palladium(II)-catalyzed C-H hydroxylation of aryl carbamates has been developed for the facile synthesis of catechols and pyrogallols. The reaction demonstrates excellent reactivity, regio- and chemoselectivity, good functional group compatibility and high yields. The practicality of this method has been proved by a gram-scale synthesis.
Yang, Xinglin,Sun, Yonghui,Chen, Zhang,Rao, Yu
supporting information
p. 1625 - 1630
(2014/06/09)
Palladium-catalyzed ortho-arylation of O-phenylcarbamates with simple arenes and sodium persulfate
By palladium catalysis, the C-H bond functionalization of O-phenylcarbamates with simple arenes has been achieved using sodium persulfate (Na2S2O8), an inexpensive, easy-to-handle, and environmentally friendly oxidant. Thi
Zhao, Xiaodan,Yeung, Charles S.,Dong, Vy M.
supporting information; experimental part
p. 5837 - 5844
(2010/06/19)
Pd(II)-catalyzed C-H activation/aryl-aryl coupling of phenol esters
(Chemical Equation Presented) Although nitrogen-containing group-directed cyclopalladation reactions have been well-known, Pd(II) insertion into C-H bonds promoted by coordination of an oxygen-only group to the palladium remains rather rare. In the present study, the first cyclopalladation complex formed from a simple phenol ester was characterized by X-ray crystallography. A promising protocol for the ortho C-H activation/aryl-aryl coupling of phenol esters that was not sensitive to moisture or air was then established. The utility of the reaction was demonstrated for the synthesis of useful phenol derivatives. Copyright
Xiao, Bin,Fu, Yao,Xu, Jun,Gong, Tian-Jun,Dai, Jian-Jun,Yi, Jun,Liu, Lei