Perfluormethyl-Element-Liganden. XL. Chrom- und Wolframpentacarbonylkomplexe von Bis(trifluormethyl)phosphanen des Typs (F3C)2PX′ (X′ = H,F, Cl,Br, I,NEt2)

Perfluormethyl-Element-Ligands. XL. Chromium and Tungsten Pentacarbonyl Complexes of Bis(trifluoromethyl)phosphanes of the Type (F₃C)₂PX′ (X′ = H, F, Cl, Br, I, NEt₂) The complexes M(CO)₅P(CF₃)₂X′ (M = Cr, W; X′ = H, F, Cl, Br, I) are obtained in preparative amounts (yields between 15 and 42%) by reacting the ligands (F₃C)₂PX′ with the adducts “M(CO)₅CH₂Cl₂”, photochemically generated from M(CO)₆ in methylene chloride. The corresponding derivatives of the aminophosphane Et₂NP(CF₃)₂ can be produced in good yields (60–75%) using the THF complexes M(CO)₅THF as precursors. The spectroscopic data (MS, IR, NMR) of the new compounds are reported. The CO valence frequencies v(CO) and the coordination shifts Δδ prove the high π-acidity of the ligands (F₃C)₂PX′.