Dual nickel- and photoredox-catalyzed reductive cross-coupling of aryl vinyl halides and unactivated tertiary alkyl bromides
作者:Weijie Yu、Long Chen、Jiasi Tao、Tao Wang、Junkai Fu
DOI:10.1039/c9cc00768g
日期:——
A novel reductive cross-coupling of arylvinylhalides and unactivated tertiary alkyl bromides has been realized via photoredox/nickel dual catalysis to produce vinyl arene derivatives bearing all-carbon quaternary centers with excellent E-selectivity. A stoichiometric metal reductant could be avoided by employing commercially available N,N,N′,N′-tetramethylethylenediamine (TMEDA) as the terminal reductant
Trifluoromethylation of Alkyl Radicals in Aqueous Solution
作者:Haigen Shen、Zhonglin Liu、Pei Zhang、Xinqiang Tan、Zhenzhen Zhang、Chaozhong Li
DOI:10.1021/jacs.7b06044
日期:2017.7.26
The copper-mediated trifluoromethylation of alkyl radicals is described. The combination of Et3SiH and K2S2O8 initiates the radical reactions of alkyl bromides or iodides with BPyCu(CF3)3 (BPy = 2,2'-bipyridine) in aqueous acetone at room temperature to afford the corresponding trifluoromethylation products in good yield. The protocol is applicable to various primary and secondary alkyl halides and
An oxidation system in which iodic acid (HIO3) is used as an oxidant in the presence of N-hydroxyphthalimide (NHPI) permitted the selective hydroxylation of tertiary C–H bonds and the lactonization of carboxylicacidscontaining a tertiarycarbon center. These reactions are operationally simple and proceed under metal-free conditions using commercially available reagents, thus offering an ideal tool
Site selective C–H oxidation of N-alkylamides and phthalimides with aqueous hydrogenperoxide catalyzed by manganese complexes is described. These catalysts are shown to exhibit substantially improved performance in product yields and substrate scope in comparison with their iron counterparts. The nature of the amide and imide group and of the N-alkyl moiety are shown to be effective tools in order to
Selective Radical Fluorination of Tertiary Alkyl Halides at Room Temperature
作者:He Chen、Zhonglin Liu、Ying Lv、Xinqiang Tan、Haigen Shen、Hai-Zhu Yu、Chaozhong Li
DOI:10.1002/anie.201708197
日期:2017.11.27
described. The halogen‐exchange fluorination proceeds efficiently in acetonitrile at roomtemperature under metal‐free conditions and exhibits a wide range of functional group compatibility. Furthermore, the reactions are highly selective in that alkyl chlorides and primary and secondary alkyl bromides remain intact. A radical mechanism is proposed for this selective fluorination.