Electrophilic coordination chemistry of group 9 and 10 perfluoroalkyl phosphine transition metal complexes.

摘要

The dimeric complex, (dfepe)2Ir2(mu-H) 3(H) (dfepe = (C2F5)2PCH2CH 2P(C2F5)2), catalytically reacted with 1 atm of ethylene at ambient temperatures to produce a mixture of trans- and cis-2-butenes and the diiridium methylallyl complex (dfepe)2Ir 2(mu-eta1,eta3-C4H 6)(mu-H)(H).;The reactivity and stability of the two iridium compounds, (dfepe)Ir(eta 3-C3H5) and (dfepe)2Ir2(mu-H) 3(H), was studied in superacid solvents (HF, SbF5). Dfepe containing transition metal complexes were shown to form stable complexes of the form [(dfepe)Ir(H)(X)(mu-H)]2 (X = F-, Sb2F11-). Additional heating resulted in (dfepe)Ir(Sb2F11)3.;The coordination chemistry of two monodentate perfluoroalkyl phosphine ligands (dfepp = (C2F5)2P(C6H 5) and dfemp = (C2F5)2P(CH3)) to platinum were studied. Synthesis of the target compound (L)2Pt(Me) 2 (L = Hemp, dfepp) was attempted to provide comparison to protonolysis of (dfepe)Pt(Me)2 and (dfepe)Pt(Me)X (X = O2CCF 3-, OSO2CF3- ). Synthesis of (dfepp)2Pt(Me)2 was not attained due to the high lability of this sterically demanding ligand, however, the smaller and more donating dfemp allowed formation of cis-(dfemp) 2Pt(Me)2. Rapid protonolysis of the first methyl group formed trans-(dfemp)2Pt(Me)X (X = O2CCF3 -, OSO2CF3-). Trans-(iPr)2Pt(Me)X, reported by Thorn, shows remarkable stability towards protonolysis for a donor phosphine complex. Preliminary studies indicate that protonolysis for trans-(dfemp) 2Pt(Me)X is much faster than predicted for the Thorn effect and faster than that reported by dfepe containing complexes. Additionally, the reactivity of (dfemp)2Pt(Me)2 and (dfemp)2Pt(Me)X with CO and H2 was studied.