Multiple metal-carbon bonds. 9. Preparation and characterization of several alkylidene complexes, M(.eta.5-C5H5)2(alkylidene)X (M = tantalum or niobium), and the x-ray structure of Ta(.eta.5-C5H5)2(CHC6H5)(CH2C6H5). An investigation of alkylidene ligand rotation

The Synthesis of Organometallic YlidesInteraction of Methylenetriphenylphosphorane with Bis(η5-cyclopentadienyl)-zirconium and -hafnium Dichlorides and the Molecular Structure of Bis(η5 -Cyclopentadienyl)chlorozirconylmethylenetriphenylphosphorane

“…the triphenylphosphorylidene moiety is displaced from the perpendicular by approximately 5.54° to the "inside". Similar displacements from the perpendicular are observed for TaCp2(CHPh)(CH2Ph) 5.7° [21], TaCp2(CHCMe3)Cl [22], 10.3° and TaCp2(CH3)(CH2) 0° [20]. The lower zlG+t is related to the extent of displacement from the perpendicular.…”

“…[21]. Similarly the <[P-C(50)-Zr] is 135.87(34)°, which is close to the same angle Ta-Ca-Cp (in the alkylidene moiety) in TaCp2(CHPh)(CH2Ph), 135.2(7)°.…”

Chemistry of 19-electron dinitrosyl complexes of tungsten and secondary carbene derivatives of iron

“…The remaining purple solid was extracted with EtgO to give a mixture of Cp(N0)2W(P(0Ph)2) and an orange product. The orange product, which 31 could not be separated from the radical was identified by its P NMR and IR spectra to be CpfNOjfCOjWfPfOPh)^), which was (Appendix (Appendix 16 The bond distances, angles (Table 1); atom positions 1); thermal parameters (Appendix 2) and structural factors…”

“…Like the NaOH-EtOH reaction, the reaction of [25] with 50% NaHmineral oil also produced a 75% yield of [30] under similar conditions. Preparation of Cp(CO)2Fe[CH(NPr')], [31] Analogous to the preparation of [30], the reaction of [27] After that time, the IR spectrum of the solution showed that ^75% of [25] During this time, MeSH liberation was evident by its odor and GC. The solvent was evaporated under reduced pressure.…”

“…In fact, studies of the alkylation of When [25] is allowed to react with a saturated NaOH-EtOH solution in CHgClg, the deprotonatlon reaction occurs immediately upon addition of the base to produce Cp(C0)2Fe(CHNCy), [30], in 78% yield. Likewise, [27] and [28] could also be deprotonated with the base, giving Cp(C0)2Fe(CHNPr') ( [31], 68%) and Cp(C0)2Fe(CHNBu^) ( [32], 76%), re spectively. These complexes [30]- [32], are vulnerable to air oxidiza tion either in solution or solid; and revert to the trans isomer of the carbene complexes in the presence of 5 eqv.…”