62049-82-5Relevant articles and documents
Microwave-promoted TBAF-catalyzed SNAr reaction of aryl fluorides and ArSTMS: An efficient synthesis of unsymmetrical diaryl thioethers
Liu, Chuanzhi,Zang, Xufeng,Yu, Baohua,Yu, Xiaochun,Xu, Qing
supporting information; experimental part, p. 1143 - 1148 (2011/07/09)
Microwave irradiation was found to promote tetrabutylammonium fluoride catalyzed nucleophilic aromatic substitution of aryl fluorides 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 and substrate scope. Georg Thieme Verlag Stuttgart - New York.
Ortho-selectivity in SNAr substitutions of 2,4-dihaloaromatic compounds. Reactions with anionic nucleophiles
Wendt, Michael D.,Kunzer, Aaron R.
scheme or table, p. 3041 - 3044 (2010/07/18)
The nucleophilic addition of organic anions to aromatic compounds with halogens positioned both ortho and para to activating groups was studied 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 maximized by using crown ethers in protic solvents. Solvent effects overall are very different from corresponding reactions with amine nucleophiles due primarily to the different charges present in the transition states, and to solvation of the nucleophile.
