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The stable compounds [NEt(4)][P(CF(3))(2)] and [18-crown-6-K][P(CF(3))(2)] were synthesized in quantitative yields by treatment of HP(CF(3))(2) with ionic cyanides at low temperature. These novel salts were characterized by multinuclear NMR spectroscopy, elemental analysis, and vibrational spectroscopy. Excellent agreement of experimental and theoretical vibrational frequencies, calculated at the B3PW91 level of theory, clearly confirms the saltlike character of these compounds. Due to their ionic nature, these salts are excellent nucleophilic reagents for the transfer of P(CF(3))(2) groups, suitable for the synthesis of chiral bidentate bis(trifluoromethyl)phosphine containing compounds.

The thermally unstable compounds Hg(CN)P(CF(3))(2) and Hg[P(CF(3))(2)](2) were obtained by reactions of mercury cyanide and bis(trifluoromethyl)phosphane in solution and characterized by multinuclear NMR spectroscopy. An increase in thermal stability is observed when the products form 18 valence electron complexes. The compounds [Hg(P(CF(3))(2))(2)(dppe)] (dppe = 1,2-bis(diphenylphosphanyl)ethane) and [Hg(P(CF(3))(2))(2)(Me(3)P)(2)] have been isolated in almost quantitative yield by reacting [Hg(CN)(2)(dppe)] or [Hg(CN)(2)(Me(3)P)(2)] with HP(CF(3))(2). [Hg(P(CF(3))(2))(2)(dppe)] crystallizes in the triclinic space group P1. The mercury atom is coordinated in a distorted tetrahedral fashion. The Hg-P(CF(3))(2) bonds, ca. 250 pm, are significantly longer than those of the mercury bis(phosphanides) Hg(PR(2))(2) with R = t-Bu, 245 pm, or SiMe(3), 241 pm. These easily accessible compounds [Hg(P(CF(3))(2))(2)(dppe)] and [Hg(P(CF(3))(2))(2)(Me(3)P)(2)] act as nucleophilic bis(trifluoromethyl)phosphane group transfer reagents.

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The use of Bu(3)SnH and Me(3)SnH in the synthesis of HP(CF(3))(2) and HP(C(6)F(5))(2) from the corresponding bromides leads to a high-yield synthesis, which additionally provides these compounds in large quantities. The pentacarbonyl tungsten complexes [W(CO)(5)PH(CF(3))(2)] and [W(CO)(5)PH(C(6)F(5))(2)] were synthesized reacting the corresponding phosphanes with [W(CO)(5)THF] and characterized by X-ray and elemental analysis as well as multinuclear NMR and mass spectroscopy. The vibrational analyses of HP(CF(3))(2) and HP(C(6)F(5))(2) and their tungsten pentacarbonyl complexes were achieved in combination with hybrid DFT calculations. The optimized structures of [W(CO)(5)PH(CF(3))(2)] and [W(CO)(5)PH(C(6)F(5))(2)] at the B3PW91 level of theory using a LanL2DZ basis and ECP at the tungsten atom and a 6-311G(3d,p) and 6-311G(d,p) basis set for the nonmetal atoms, respectively, yield an impressively good agreement between experimental and theoretical geometric parameters. An increased pi-acidity of HP(CF(3))(2) in comparison with HP(C(6)F(5))(2) and HPPh(2) is discussed in the context of vibrational analysis, X-ray structural investigations, and theoretical calculations.