25074-67-3Relevant articles and documents
Copper-Catalyzed One-Pot Synthesis of Dibenzofurans, Xanthenes, and Xanthones from Cyclic Diphenyl Iodoniums
Zhu, Daqian,Li, Min,Wu, Zhouming,Du, Yongliang,Luo, Bingling,Huang, Peng,Wen, Shijun
supporting information, p. 4566 - 4571 (2019/07/09)
Oxygenation of cyclic diphenyl iodoniums (CDPIs) with varied medium-ring sizes has been fully investigated. This practical copper-catalyzed tandem reaction of CDPIs with water as the oxygen source enables the construction of derivatised dibenzofurans and xanthenes at moderate to good yields. Moreover, structurally important xanthones are also successfully accessed under the oxygenation conditions with additional TEMPO.
Reaction Mechanism of 4-Chlorobiphenyl and the NO3 Radical: An Experimental and Theoretical Study
Shi, Jin,Bi, Wenlong,Li, Shenmin,Dong, Wenbo,Chen, Jianmin
, p. 3461 - 3468 (2017/06/09)
Experiment and theoretical chemistry calculations were conducted to elucidate the mechanism of the reaction between 4-chlorobiphenyl (4-CB) and the NO3 radical. The degradation of PCBs was investigated mechanistically through transient absorption spectroscopy technology and high-accuracy theoretical calculation by using 4-CB as the model. Laser flash photolysis (LFP) experiments were performed at 355 nm. The main intermediate was analyzed through transient absorption spectroscopy and identified to be a charge transfer complex (CTC). The final products were identified through GC-MS analysis. The ground states and excited states of the reactants were calculated through density functional theory (DFT) method. The absorption bands at 400 and 700 nm show good agreement with the experimental results. The ratio of absorbance at 400 and 700 nm is 1.6, and the experimental value is 1.8. Analysis of the charge population indicated that one unit charge transfer from 4-CB to NO3. The entire reaction process was divided into two phases. In the first phase, the CTC intermediate was formed by electrostatic attraction between 4-CB and the NO3 radical. In the second phase, the most important channel of subsequent reactions is the σ-complex as an intermediate formed by N-C coupling. The final product 4-chloro,2-nitrobiphenyl was generated with the breakage of BC-H and BN-O, and benzene derivatives were formed by other channels.
Synthesis of dibenzofurans via palladium-catalyzed phenol-directed C-H activation/C-O cyclization
Xiao, Bin,Gong, Tian-Jun,Liu, Zhao-Jing,Liu, Jing-Hui,Luo, Dong-Fen,Xu, Jun,Liu, Lei
supporting information; experimental part, p. 9250 - 9253 (2011/08/06)
A practical, Pd(0)/Pd(II)-catalyzed reaction was developed for phenol-directed C-H activation/C-O cyclization using air as an oxidant. The turnover-limiting step of the process was found to be C-O reductive elimination instead of C-H activation. This reaction can tolerate a variety of functional groups and is complementary to the previous methods for the synthesis of substituted dibenzofurans.
