<正>Transition metal-catalyzed N-alkylation of amines/amides 2 with alcohols 1,a relatively environmentally -be...
Qing Xu,~* Chuanzhi Liu,Shiheng Liao,Lan Jiang,Qiang Li,Sunlin Feng and Xiaochun Yu College of Chemistry and Materials Engineering,Wenzhou University,Wenzhou 325035
Possibly because homogeneous palladium catalysts are not typical borrowing hydrogen catalysts and ligands are thus ineffective in catalyst activation under conventional anaerobic conditions, they had not been used in the N-alkylation reactions of amines/amides with alcohols in the past. By employing the aerobic relay race methodol- ogy with Pd-catalyzed aerobic alcohol oxidation being a more effective protocol for alcohol activation, ligand-free homogeneous palladiums are successfully used as active catalysts in the dehydrative N-alkylation reactions, giving high yields and selectivities of the alkylated amides and amines. Mechanistic studies implied that the reaction most probably proceeds via the novel relay race mechanism we recently discovered and proposed.
Tetrabutylammonium fluoride (TBAF) effectively facilitated a denitrative substitution reaction of electron-deficient nitroarenes with phenylthiotrimethylsilane (PhSTMS) under mild and base-free neutral conditions at room temperature, providing a practical and efficient synthesis of useful unsymmetrical diaryl thioethers. Nitroarenes bearing ortho- and para-positioned electron-withdrawing groups are the most reactive substrates, indicating that this reaction most possibly proceeded via the nucleophilic aromatic substitution (SNAr) mechanism.