Coupling of arylboronic acids with benzyl halides or mesylates without adding transition metal catalysts
作者:Guojiao Wu、Shuai Xu、Yifan Deng、Chaoqiang Wu、Xia Zhao、Wenzhi Ji、Yan Zhang、Jianbo Wang
DOI:10.1016/j.tet.2016.10.031
日期:2016.12
We report herein a transition-metal-free coupling reaction of arylboronic acids with benzyl halides and mesylates for the construction of C(sp2)C(sp3) bonds. A unique feature of this coupling reaction is the formation regioisomers in some cases. Mechanistic studies suggest that this reaction may proceed via an unprecedented Friedel–Crafts-type reactionpathway under base conditions with the assistance
Au-Catalyzed Biaryl Coupling To Generate 5- to 9-Membered Rings: Turnover-Limiting Reductive Elimination versus π-Complexation
作者:Tom J. A. Corrie、Liam T. Ball、Christopher A. Russell、Guy C. Lloyd-Jones
DOI:10.1021/jacs.6b10018
日期:2017.1.11
The intramolecular gold-catalyzed arylation of arenes by aryl-trimethylsilanes has been investigated from both mechanistic and preparative aspects. The reaction generates 5- to 9-membered rings, and of the 44 examples studied, 10 include a heteroatom (N, O). Tethering of the arene to the arylsilane provides not only a tool to probe the impact of the conformational flexibility of Ar-Au-Ar intermediates
Efficient palladium-catalyzed C(sp<sup>2</sup>)–H activation towards the synthesis of fluorenes
作者:Juan Song、Yali Li、Wei Sun、Chenglong Yi、Hao Wu、Haotian Wang、Keran Ding、Kang Xiao、Chao Liu
DOI:10.1039/c6nj02033j
日期:——
protocol for the synthesis of fluorene derivatives has been developed through palladium-catalyzed cyclization of 2′-halo-diarylmethanes via activation of arylic C–H bonds. The reactions occurred smoothly and allowed both electron-rich and electron-deficient substrates to convert into their corresponding fluorenes in good to excellent yields. Studies revealed that this Pd-catalyzedcyclization was also available
Bismuth-catalyzed synthesis of anthracenes via cycloisomerization of o-alkynyldiarylmethane
作者:Jungmin Park、Hyuck Choi、Deug-Chan Lee、Kooyeon Lee
DOI:10.1016/j.tetlet.2015.10.111
日期:2015.12
In this study, anthracenes were efficiently synthesized from o-alkynyldiarylmethane using a novel method that exploits the synergistic effect between Bi(OTf)3 as the catalyst, and trifluoroacetic acid (TFA). Through this reaction, we achieved the rapid and efficient synthesis of anthracenes bearing various functional groups under mild conditions.