and kinetically competent catalysts for this transformation. The fleeting transmetalation intermediate has been successfully synthesized through an alternative synthetic organometallic pathway at lower temperature, allowing for in situ NMR study of the C–N bond reductive elimination step. This study addresses key factors governing the mechanism of the nickel-catalyzed Buchwald–Hartwig amination process
Palladium-catalyzed intermolecular transthioetherification of aryl halides with thioethers and thioesters
作者:Yahui Li、Gao Bao、Xiao-Feng Wu
DOI:10.1039/c9sc05532k
日期:——
Functional group transfer reactions are an important synthetic tool in modern organic synthesis. Herein, we developed a new palladium-catalyzed intermolecular transthioetherification reaction of arylhalides with thioethers and thioesters. The synthetic utility and practicality of this catalytic protocol are demonstrated in a wide range of successful transformations (>70 examples). This catalytic protocol
A nickel-catalyzed aryl thioether metathesis has been developed to access high-value thioethers. 1,2-Bis(dicyclohexylphosphino)ethane (dcype) is essential to promote this highly functional-group-tolerant reaction. Furthermore, synthetically challenging macrocycles could be obtained in good yield in an unusual example of ring-closingmetathesis that does not involve alkene bonds. In-depth organometallic
carbon–heteroatom (C–P, C–O, C–S, and C–N) bonds via C–N cleavage of benzyl ammoniumsalts under transition-metal-free conditions was reported. The combination of t-BuOK and 18-crown-6 enabled a wide range of substituted benzyl ammoniumsalts to couple readily with different kinds of heteroatom nucleophiles, i.e. hydrogen phosphoryl compounds, alcohols, thiols, and amines. Good functional group tolerance was demonstrated
Fluorium-Initiated Dealkylative Cyanation of Thioethers to Thiocyanates
作者:Yang Chen、Hongyi Qi、Ning Chen、Demin Ren、Jiaxi Xu、Zhanhui Yang
DOI:10.1021/acs.joc.9b00965
日期:2019.7.19
Thioethers are converted to thiocyanates via fluorium-initiated dealkylative cyanation. Selectfluor is used as the oxidant, and trimethylsilyl cyanide is used as the cyanation reagent. The well-streamlined procedure is user-friendly, operationally simple, and step-economical. The current mechanistic studies show that the sulfur radical cation and cyano radical are both involved. They combine to deliver