Polyfluoroorganotrifluoroborates and -difluoroboranes: interesting materials in fluoroorgano and fluoroorgano-element chemistry

The aimed introduction of the polyfluoroorgano groups (4-C₅F₄N), C₆F₁₃C₂H₄, and C₂F₅ into methoxy group-containing boron electrophiles is reported. The new compounds obtained after transformations K(4-C₅F₄N)BF₃], (4-C₅F₄N)BF₂, KC₆F₁₃C₂H₄BF₃], C₆F₁₃C₂H₄BF₂, K(C₂F₅)₂B(OMe)₂], and K(C₂F₅)₂BF₂] were isolated and characterised. Additionally some of their precursors as there are Li(4-C₅F₄N), Li(4-C₅F₄N)B(OMe)₃], (4-C₅F₄N)B(OH)₂ and the by-products Li(4-C₅F₄N)₂B(OMe)₂], (4-C₅F₄N)₂BOH, and K(4-C₅F₄N)₂BF₂] are described. The usefulness of polyfluoroorganodifluoroboranes for introducing polyfluoroorgano groups into hypervalent FEF bonds is demonstrated by the synthesis of C₆F₅(4-C₅F₄N)I]BF₄] and p-FC₆H₄(trans-CF₃CFCF)I]BF₄].