Thorium organometallic complexes

Bilinear chemometrics methods, 6 39-57 Billet products, titanium, 24 858 Bill of Material, 15 460, 470 Bills of lading, 25 330 Bimetal complexes, 16 88 Bimetallic deactivation processes, 16 93-94 Bimetallic fluorides, 15 396 Bimetallic metal nitrides, 17 199 Bimetallic organometallic uranium complexes, 25 442 Bimetallic organometallic thorium complexes, 24 773-774... 

Coordination Complexes. The coordination and organometallic chemistry of thorium is dominated by the extremely stable tetravalent ion. Except in a few cases where large and sterically demanding ligands are used, lower thorium oxidation states are generally unstable. An example is the isolation of a molecular Th(III) complex [107040-62-0], Th[t -C5H3(Si(CH3)3)2]3 (25). Reports (26) on the synthesis of soluble Th(II) complexes, such as... 

Bimetallic Complexes. There are two types of bimetallic organometallic thorium complexes those with, and those without, metal—metal interactions. Examples of species containing metal—metal bonds are complexes with Fe or Ru carbonyl fragments. Cp ThX(CpRu(CO)2), where X = Cl or I, and Cp 3Th(CpM(CO)2), where M = Fe or Ru, have both been prepared by interaction of Cp2ThX2 or Cp ThCl [62156-90-5], respectively, with the anionic metal carbonyl fragment. These complexes contain very polar metal—metal bonds that can be cleaved by alcohols. 

That such monohapto organometallics are not unique to uranium was demonstarted by the high yield synthesis of the thorium (IV) analogs (Reaction 2) (16,17). These complexes have even greater thermal stabil-... 

The formation of alkyne oligomers that are concomitantly formed in the hydroamination reactions catalyzed by the thorium complexes indicates that two possible different complexes can be considered as active, conceivably with inter-conversion causing the occurrence of the two parallel processes. The discernment between these two most probable mechanistic pathways to find the key organometallic intermediate, responsible for the hydroamination process, was achieved by kinetic and thermodynamic studies (Scheme 5). The first pathway proposed the insertion of an alkyne into a metal-imido (M=N) bond, as observed for early transition metal complexes [101]. The second pathway suggested the insertion of an alkyne into a metal-amido bond, as found in some lanthanide compounds [39, 58, 84, 85]... 

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