Synthesis and Structure of Tetraphenylphosphonium Carboxylates

Hydrates of tetraphenylphosphonium carboxylates were synthesized by the reaction of equimolar amounts of pentaphenylphosphorus with 2-methoxybenzoic, 2-nitrobenzoic, and maleic acids in benzene. The product of the pentaphenylphosphorus reaction with tetrafluorophthalic acid (mole ratio 2: 1) is bis- (tetraphenylphosphonium) tetrafluorophthalate hydrate. According to the X-ray analysis data, crystals of tetraphenylphosphonim carboxylates are formed by tetraphenylphosphonim tetrahedral cations and single- or double-charged carboxylate anions. Structural organization of the crystals is determined by C–H···O weak hydrogen bonds formed with the participation of carboxylate groups and water molecules or manifold C–H···F interactions between cations and anions.