Thorium complex

There is Httie known chemistry of tetrakis-Cp thorium complexes. Pseudotetrahedral molecules, (rj-ring) Tb (15), where ring = Cp [1298-75-5] or Ind [11133-17-6], have a measurable dipole, resulting from deviation of symmetry (88). Difference of coordination environments, eg, v] in the indenyl system and in the Cp system, appears to indicate great steric crowding about the thorium center, which probably limits the reactivity and synthetic derivatization of these complexes. 

Bimetallic Complexes. There are two types of bimetaUic organometaUic thorium complexes those with, and those without, metal—metal interactions. Examples of species containing metal—metal bonds are complexes with Ee or Ru carbonyl fragments. Cp ThX(CpRu(CO)2), where X = Cl or 1, and Cp7Th(CpM(CO)2), where M = Ee or Ru, have both been prepared by interaction of CP2TI1X2 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. 

Thorium complexes, 3, 1131-1215 groundwaters geochemistry, 6. 852 polypyrazolylborates, 2. 255 Thorium(IV) complexes cupferron, 2, 512 peptides... 

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... 

Thorium (Th), 7 463-491, 464t, 27 286, 287, 24 753-782. See also Thorium complexes Thorium compounds Thorium isotopes... 

Thorium carbides, 24 761, 4 689—690 Thorium carbonate, 24 765 Thorium carboxylates, 24 768-769 Thorium chlorides, 24 762-763 Thorium complexes allyl, 24 773... 

Following the characterization of U(COT)2, the analogous thorium complex was synthesized 12). Its physical and chemical properties were so different from those of the uranium compound that initially there was question as to whether the complex had the same -sandwich structure. The X-ray structure anal5 is however showed it to be isostructural with U(COT)2 11). Subsequently, Pu(COT)2 13), Np(COT) 13), and Pa(COT)2 14, 15) have been prepared and their X-ray powder patterns show them all to be isostructural with U(COT)2. 

The tetraallylic complexes of thorium and uranium can be isolated as red sohds and are stable to 0° and — 20°C, respectively, whereas the uranium homoalkyls defy isolation at temperatures as low as — 80°C. The greater stability of the thorium complex has been attributed partially to the great instability of Th(III) as compared with U(III) (96). The tc mode of bonding and the resultant increase in coordination number to eight of the allyl complexes significantly increases their thermal stability relative to the uranium homoalkyls. 

The four compounds with R = H are isostructural, and in the thorium complex the eight-coordinate metal atom lies at the centre of a distorted square antiprismatic array of four N and four O atoms. In benzene solution, however, the molecular weights of the complexes with R = H indicate that they are dimers, whereas those with R = Me are monomers.166... 

Di(carbene)gold(I) salts, oxidation, 2, 293—294 Dicarbido clusters, with decarutheniums, 6, 1036 Dicarbollide amides, with tantalum, 5, 184 Dicarbollide thorium complexes, synthesis and characterization, 4, 224—225 Dicarbollyl ligands, in nickel complexes, 8, 185 Dicarbonyl complexes arylation with lead triacetates diastereoselectivity, 9, 389 enantioselectivity, 9, 391 mechanisms, 9, 387 reaction examples, 9, 382 indium-mediated allylation, 9, 675 with iridium, 7, 287 reductive cyclization, 10, 529 in Ru and Os half-sandwiches, 6, 508 with Zr—Hf(II), 4, 700... 

Among mixed-ligand cyclo-octatetraene complexes, the U, Th, Pa, Np, and Pu complexes [(r -Cx 11x)An(p-SPr)2]2 were reported, which can be prepared by reacting the thiol with U(COT)(BH4) [399a], Reduction of the bulky 8-annulene thorium complex [Th COT(TBS)2 2] [COT(TBS)2 = CxIIfi(/-BuMc2Si)2-l,4] by potassium... 

A red paramagnetic (l,4-diazabutadiene)thorium complex 989 (monoclinic, space group P2i/ri) was the first obtained diazabutadiene (DAB) derivative of an actinide metal [459]. It was prepared in THF at — 80°C from [ (tren )ThCl 2], containing amino-tm ethyl(trimethylsilyl)amido (tren ) ligand which provides a suitable environment for the stabilization of the product (5.74) ... 

Some uranium and thorium complexes with the above ligands are presented in Table 5.17. 

Thorium complex compounds, nonelectrolytes, with acetylacetone, 2 123... 

Cyclopentadienyl and Substituted Cyclopentadienyl Complexes. Thorium complexes containing cyclopentadienyl rings (Cp),... 

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