Patent ID: 8829188

Claim:
A compound formula I [P(R f ) n F 5-n D] − I, where R f in each case, independently of one another, denotes a straight-chain or branched fluoroalkyl group having 1 to 8 C atoms, n denotes 1, 2 or 3 and D denotes a Lewis base selected from triphenylphosphine oxide, trimethyl phosphate, aromatic amines, dialkyl ethers, aromatic or aliphatic tertiary phosphines, dialkylformamides, dialkylacetamides or N-alkyl-2-pyrrolidones, where said alkyl groups have, in each case independently of one another, 1 to 8 C atoms, or a tautomer or stereoisomer thereof, including mixtures thereof in all ratios.