Improved Access to Organo-Soluble Di- and Tetrafluoridochlorate(I)/(III) Salts.

A facile one-pot gram-scale synthesis of tetraalkylammonium tetrafluoridochlorate(III) [cat][ClF ] ([cat]=[NEt Me] , [NEt ] ) is described. An acetonitrile solution of the corresponding alkylammonium chloride salt is fluorinated with diluted fluorine at low temperatures. The reaction proceeds via the [ClF ] anion which is structurally characterized for the first time. The potential application of [ClF ] salts as fluorinating agents is evaluated by the reaction with diphenyl disulfide, Ph S , to pentafluorosulfanyl benzene, PhSF . The CN moieties in acetonitrile and [B(CN) ] are transferred in CF groups. Exposure of carbon monoxide, CO, leads to the formation of carbonyl fluoride, COF , and elemental gold is dissolved under the formation of tetrafluoridoaurate [AuF ] .