Details

Autor(en) / Beteiligte

• Föhrenbacher, Steffen A.
• Krahfuss, Mirjam J.
• Zapf, Ludwig
• Friedrich, Alexandra
• Ignat'ev, Nikolai V.
• Finze, Maik
• Radius, Udo

Titel

Tris(pentafluoroethyl)difluorophosphorane: A Versatile Fluoride Acceptor for Transition Metal Chemistry

Ist Teil von

• Chemistry : a European journal, 2021-02, Vol.27 (10), p.3504-3516

Ort / Verlag

Germany: Wiley Subscription Services, Inc

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Fluoride ion from different types of transition metal fluoride complexes [LnMF] (M=Ti, Ni, Cu) by the Lewis acid tris(pentafluoroethyl)difluorophosphorane (C2F5)3PF2 to yield cationic transition metal complexes with the tris(pentafluoroethyl)trifluorophosphate counterion (FAP anion, [(C2F5)3PF3]−) is reported. (C2F5)3PF2 reacted with trans‐[Ni(iPr2Im)2(ArF)F] (iPr2Im=1,3‐diisopropylimidazolin‐2‐ylidene; ArF=C6F5, 1 a; 4‐CF3‐C6F4, 1 b; 4‐C6F5‐C6F4, 1 c) through fluoride transfer to form the complex salts trans‐[Ni(iPr2Im)2(solv)(ArF)]FAP (2 a‐c[solv]; solv=Et2O, CH2Cl2, THF) depending on the reaction medium. In the presence of stronger Lewis bases such as carbenes or PPh3, solvent coordination was suppressed and the complexes trans‐[Ni(iPr2Im)2(PPh3)(C6F5)]FAP (trans‐2 a[PPh3]) and cis‐[Ni(iPr2Im)2(Dipp2Im)(C6F5)]FAP (cis‐2 a[Dipp2Im]) (Dipp2Im=1,3‐bis(2,6‐diisopropylphenyl)imidazolin‐2‐ylidene) were isolated. Fluoride ion from [(Dipp2Im)CuF] (3) in CH2Cl2 or 1,2‐difluorobenzene led to the isolation of [{(Dipp2Im)Cu}2]2+2 FAP− (4). Subsequent reaction of 4 with PPh3 and different carbenes resulted in the complexes [(Dipp2Im)Cu(LB)]FAP (5 a–e, LB=Lewis base). In the presence of C6Me6, fluoride transfer afforded [(Dipp2Im)Cu(C6Me6)]FAP (5 f), which serves as a source of [(Dipp2Im)Cu)]+. Fluoride ion of [Cp2TiF2] (7) resulted in the formation of dinuclear [FCp2Ti(μ‐F)TiCp2F]FAP (8) (Cp=η5‐C5H5) with one terminal fluoride ligand at each titanium atom and an additional bridging fluoride ligand. A series of titanium, nickel, and copper complexes stabilized by the weakly coordinating anion (WCA) [(C2F5)3PF3]− (FAP anion) was obtained on reaction of the parent fluoride complexes with the strong Lewis acid (C2F5)3PF2. The reaction products depend on the solvent used or additional Lewis bases present during the fluoride transfer from the metal complexes to the phosphorane.