Pentakis(methoxycarbonyl)cyclopentadiene Chemistry. XIII. Some Metal Derivatives of 1-Methyl-2,3,4,5-tetrakis(methoxycarbonyl)cyclopentadiene. X-Ray Structure of Au[C₅Me(Co₂Me)₄](PPh₃)

Abstract

Reactions of HC₅Me(CO₂Me)₄ or TI[C₅Me(CO₂Me)₄] with appropriate precursors have afforded the compounds ML₂{C₅Me(CO₂Me)₄}₂ (M = Mn , L = H₂O; M = Cu, L = MeOH ), Rh (ŋ⁴C⁸H₁₂ )}ŋ^{5 -}C₅Me(CO₂Me)₄}, Rh {C₅Me(CO₂Me)₄]₂,RU(ŋ-C₅H₅){η⁵(C₅Me(CO₂Me)₄}, Cu{C₅Me(CO₂Me)₄}-(PPh₃)₂ and M{C₅Me(COP₂Me)₄}(PPh₃)(M=Ag or Au). There appear to be no significant differences between these compounds and analogous species derived from HC₅(CO₂Me)₅, except for the expected spectroscopic changes.

The molecular structure of Au{C₂Me(CO₂Me)₄}(PPh₃) closely resembles that of Au{C₅(CO₂- Me)₅}(PPh₃); the methyl group is on the ring carbon adjacent to that which most closely interacts with the Au(PPh₃) group. Crystals are monoclinic, space group P2₁/c, with a 10.313(2), b 10-388(3), c 28.637(11)Å, β 97.01(3)º, Z 4; 3571 data with I> 3σ) were refined to R 0.037, R′0.033.