Hydrocarbyl bis-

Hydrocarbonyl compounds, lanthanide complexes, 4, 4 ( -Hydrocarbyl)bis(zirconocene), preparation, 4, 906 Hydrocarbyl-bridged cyclopentadienyl-amido complexes, with Zr(IV), 4, 864 Hydrocarbyl complexes bis-Cp Ti hydrocarbyls reactions, 4, 551 structure and properties, 4, 551 synthesis, 4, 542 cobalt with rf-ligands, 7, 51 cobalt with rf-ligands, 7, 56 cobalt with ]4-ligands, 7, 59 cobalt with rf-ligands, 7, 71 heteroleptic types, 4, 192 homoleptic types, 4, 192 into magnetic metal nanoparticles via ligand stabilization, 12, 87 via polymer stabilization, 12, 87 into noble metal nanoparticles... 

Babu RPK, Mcdonald R, Decker SA, Klobukowski M, Cavell RG (1999) New zirconium hydrocarbyl bis (phosphoranimino) pincer carbene complexes. Organometallics 18 4226 229. doi 10.1021/om9901473... 

Following the synthesis of the first methyl-palladium NHC complexes it was subsequently found that the complexes undergo a facile thermal decomposition process in which the NHC is lost as 2-methylimidazolium salt and the Pd is rednced to Pd(0) (Scheme 13.1) [15-17]. In ensuing studies investigating the reaction behavionr of a range of hydrocarbyl Pd and Ni carbene complexes, it was found that the decomposition reaction is ubiquitous. It occurs with varying ease, for mono-NHC, bis-NHC and donor functionalised-NHC complexes [16-23]. 

An alternative route to poly(m-carborane-siloxane) rubbers is via the condensation reaction between w-carborane di-hydrocarbyl-disilanol and a bis-ureidosilane.20 This mild reaction allows the incorporation of desired groups into the polymer via both the dihydrocarbyl-disilanol and the bis-ureidosilane (see scheme 8). The first step involves the formation of the carborane silanol from the butyl lithium carborane derivative. The bis-ureidosilane is prepared from the phenyl isocyanate (see step 2), and the final step involves reacting the dihydrocarbyl-disilanol with bis-ureidosilane. 

As already noted, the carbonylation of bis(pentamethyl-cyclopentadienyl) actinide hydrocarbyls is irreversible in the cases studied thus far. Thus, thermolysis does not result in CO loss, but rather in interesting chemical reactions. Thermolysis of 1 ( 5) in toluene solution results in hydrogen atom migration to yield an enolate (eq.(5)). NMR studies establish that eq.(5) is essentially quantitative, and that the stereochemical course... 

The reaction conditions of example 1 were repeated using a different hydrocarbyl aluminum activator in a 4 1 molar ratio to chromium(III) tris(bis(trimethylsilyl)-amide). Reactions were conducted at an ethylene pressure of 100 psi at 70°C for 60 minutes. Neither 1-butene nor 1-decene was detected in the product mixture. A summary of reaction scooping is provided in Table 1. 

Bis-phenoxo hydrocarbyl complexes, with Ti(IV), 4, 331 Bisphenoxo ligands, on mono-Cp Ti(IV) complexes, 4, 485 Bis(phenoxy-aldehyde) dichlorides, with Zr(IV), 4, 787 Bis(phenoxy-amino) catalysts, in propylene polymerization,... 

Of great importance as precatalysts in organolanthanide-catalyzed processes are lanthanide hydrocarbyls containing the bulky bis(trimethylsilyl)methyl ligand. They are also the most suitable precursors for the preparation of the dimeric hydrides [(C5Me5)2Ln(/t-H)]2. Such compounds can be isolated completely free of coordinating solvents and alkali metal halides Eq. (2) [19-25. ... 

Higher 43-hydrocarbyl derivatives of transition metals can be obtained by partial protolysis of the bis(7i-allyl)metal compounds formed from cyclo-octa-1,5-diene metal complexes and 1,3-butadiene with one equivalent of the Bronsted acid in the presence of the proper ligand in a polar solvent at lowered temperature (e.g. — 40°C). For instance, Ni [43-(CxHn)l and Ni—[43-(Ci2Hig)] derivatives have been yielded by the reaction of Ni(CxH 2)2 [(Ni(Cod)2] with 1,3-butadiene (C4H6), followed by treatment with a Bronsted acid, according to scheme (1) [132] and scheme (2) [37] respectively ... 

Jeske, G, Lauke, H., Mauermann, H. etal. (1985) Highly reactive organolanthanides. Systematic routes to and olefin chemistry of early and late bis(pentamethylcyclopentadienyl) 4f hydrocarbyl and hydride complexes. Journal of the American Chemical Society, 107, 8091. 

Cui, C., Shafir, A., Reeder, C.L. et al. (2003) Highly isospecific polymerization of methyl methacrylate with a bis(pyrrolylaldiminato)samarium hydrocarbyl complex. Organometallics, 22, 3357. 

The allenylidene [M=C=C=CR R ] unit represents a member of the class of carbon-rich unsaturated hydrocarbyl fragments, and it is capable of binding one to four metal centers. In sharp contrast to the rapidly developing chemistry of mononuclear allenylidene complexes, the scarcity of bi- and polynuclear species of this type has hindered the development of an extensive chemistry. Selected examples from the allenylidene literature are cited in this article owing to the close structural analogy with allenyl derivatives. The reader is referred to a review article by Bruce covering the relevant literature of this metallacumulene up to 1989 (la). 

The stereocontrol in the polymerization of MMA mediated by chiral organolanthanide metallocenes has been investigated. Flydride, hydrocarbyl, and amido bis(cyclopentadienyl) complexes (Scheme 268) were used as precatalysts for the processes. The achiral hydride precatalysts yielded syndiotactic PMMA with narrow polydispersities (Mw/Mn = 1.02-1.05). The polydispersities of PMMA from the chiral and achiral hydrocarbyl precatalysts are larger then those from the hydride precatalysts, and amide precatalysts gave the largest polydispersities.982... 

Bis-phenoxo hydrocarbyl five-coordinated titanium complexes (Scheme 21) have been synthesized and spectroscopically characterized. The molecular structure determined by X-ray diffraction shows the metal to have a distorted trigonal-bipyramidal coordination geometry. Cationic four-coordinate derivatives can be generated by reaction of the methyl derivatives with B(C6F5)3. These cationic species undergo stoichiometric insertions of ethylene and propylene into the Ti-C bond.67... 

---