DMF‐Promoted S─Si Bond Activation Leading to Efficient Activator‐ and Catalyst‐Free C‐S Couplings of Thiosilanes and Organohalides

Abstract It was unexpectedly found that, if performed in amide type solvents such as DMF, nucleophilic substitution reaction of heteroaryl halides and thiosilanes could proceed effectively without any activator or catalyst. Mechanistic studies and literature findings implied that a DMF‐promoted direct S─Si bond activation of thiosilanes is most likely the driving force to promote the reaction. This protocol could be extended to alkyl halides and some electron‐deficient aryl halides, showing relatively broad scope of the substrates. This method may be a more convenient and practical way for preparing several types of unsymmetrical thioethers.