Amino-Directed Rh<sup>III</sup>-Catalyzed CH Activation Leading to One-Pot Synthesis of NH Carbazoles
作者:Qibai Jiang、Dandan Duan-Mu、Wei Zhong、Hao Chen、Hong Yan
DOI:10.1002/chem.201203856
日期:2013.2.4
One‐pot synthesis: An efficient amino‐directed one‐pot synthesis of NHcarbazoles from unprotected 2‐aminobiaryl compounds is reported. The free amino unit acts as both a directing group for ortho CHactivation and a functional group for construction of an N‐heterocyclic ring (see scheme).
The first example of the palladium-catalyzed primary amine-directed C(sp2)–H alkynylation of biaryl-2-amines has been developed by using (bromoethynyl)triisopropylsilane as an alkynylating reagent. This protocol exhibits a broad substrate scope, excellent regioselectivity and gram-scale synthesis. Significantly, the versatility of this straightforward method was further demonstrated by controlled mono-
An efficient synthesis of free (NH)-phenanthridinones through Pd-catalyzed C(sp(2))-H aminocarbonylation of unprotected o-arylanilines under an atmospheric pressure of CO has been developed. Some ortho heteroarene substituted anilines as well as N-alkyl protected o-arylanilines are also suitable substrates for this C-H aminocarbonylation reaction.
The iridium-catalyzed dehydrogenative cyclization of 2-aminobiphenyls proceeds smoothly in the presence of a copper cocatalyst under air as a terminal oxidant through intramolecular direct C-H amination to produce N-H carbazoles. A similar iridium/copper system can also catalyze the unprecedented dimerization reaction of 2-aminobiphenyl involving 2-fold C-H/N-H couplings.
作者:Wenguang Li、Wenqi Chen、Bang Zhou、Yankun Xu、Guobo Deng、Yun Liang、Yuan Yang
DOI:10.1021/acs.orglett.9b00690
日期:2019.4.19
A novel palladium-catalyzed interannular selective C-H silylation of 1,1'-biaryl-2-acetamides is described. The combination of palladium catalyst with copper oxidant enables meta- or ortho-selective C-H silylation by employing hexamethyldisilane as a trimethylsilyl source, which relies on the control of NBE derivatives as a switch, thus providing straightforward access to divergent silicon-containing 1,1'-biaryl-2-acetamides.