Microwave irradiation was found to promote tetrabutylammonium fluoride catalyzed nucleophilic aromatic substitution of arylfluorides and arylthiotrimethylsilanes, affording high yields of unsymmetrical diaryl thioethers efficiently under mild, transition-metal- and base-free conditions. Microwave showed unusual improvement on the reaction in not only the conditions and reaction rate, but also in selectivity
TBAF-Catalysed Facile Synthesis of Unsymmetrical Diaryl Thioethers via Mild S<sub>N</sub>Ar Reactions
作者:Baohua Yu、Xufeng Zang、Xiaochun Yu、Qing Xu
DOI:10.3184/030823410x12766133486958
日期:2010.6
By using tetrabutylammonium fluoride as the catalyst, the synthesis of unsymmetrical diaryl thioethers could be easily achieved in high yields via a mild nucleopilic aromatic substitution reaction of aryl fluorides and phenylthiotrimethylsilane.
Ortho-selectivity in SNAr substitutions of 2,4-dihaloaromatic compounds. Reactions with anionic nucleophiles
作者:Michael D. Wendt、Aaron R. Kunzer
DOI:10.1016/j.tetlet.2010.03.124
日期:2010.6
in a variety of solvents. Substrates showed strong preferences for ortho substitution in most cases. Evidence is presented for activating group-dependent coordination, which contributes to very high ortho-selectivity in nonpolar solvents. This also drives the overall reaction rate in these solvents, and is of close to the same magnitude of rate increase derived from polar solvents. para-Products are