Sb complex

Drysdale CM, McGraw DW, Stack CB, Stephens JC, Judson RS, Nandabalan K, Arnold K, Ruano G, Liggett SB. Complex promoter and coding region fl2-adrenergic receptor haplotypes alter receptor expression and predict in vivo responsiveness. Proc Natl Acad Sci USA 2000 97 10483-10488. 

The crystal structure of /i-oxo-bis[tris(p-chlorophenyl)(l,l,l-trifluoro-2,4-pen-tanedionato-0,0 )antimony(V)] 1/2 chloroform has been determined375. The compound crystallizes in triclinic system, space group PI. The binuclear Sb-complex consists of two distorted octahedra joined by an O atom which is situated at inversion centre the Sb-O-Sb bridge is linear. This seems to be the first example of a linear Sb-O-Sb linkage. The bridged oxygen and one of the oxygens of/3-diketone occupy trans-positions. The/3-diketonate forms two distinct Sb-0 bonds ... 

The number of SB complexes crystallographically characterized is very broad, however, comparatively only a limited number of crystal structures of metal-free SBs has been reported.8-15 In those cases in which the structures of both the metal-free SB and their complexes are available, a comparative analysis can be made to establish how the conformation of the ligand is affected upon coordination to a metal. Several representative examples have been selected for this chapter.16-19... 

Numerous reviews dealing with SB complexes have appeared.1-3,7,20-31 Other reviews prior to 1982 can be found in the first edition.7... 

Since the free SBs are not always stable, many SB complexes are prepared by template synthesis which implies carrying out the condensation reaction in the presence of a metal ion. This is a very common method for the preparation of macrocyclic SB complexes.2,3 In this case large alkaline earth metal cations (i.e., Ba11, lanthanoids, or Pb11) have proved to be efficient templates. The size... 

The spin-crossover phenomenon in tridentate SB complexes of Fe111, Fe11 and Co11 has been extensively investigated.70-72 Iron(III) SB complexes having a (N20)2 donor set may exhibit spin-crossover phenomena.73-77 The (N20)2 donor set is provided by coordination of two tridentate N20 SBs. Thus, a thermal-induced spin-crossover phenomenon has been observed for Fe111 complexes of the half unit (15a)77 and for other N20 tridentate SBs.76... 

N2S2 SBs bearing sterically protected thiol groups as well as imine, imidazole, and thioether groups113 and other N2S2 SB complexes have also been prepared.114,115... 

Jacobsen reported in 1990 that Mnm complexes of chiral salen ligands (41) were the most efficient catalysts available for the enantioselective epoxidation of alkyl- and aryl-substituted olefins.118 This stimulated a rapid development in the chemistry and applications of chiral SB complexes, which offer promising catalytic applications to several organic reactions, such as enantioselective cyclopropanation of styrenes, asymmetric aziridination of olefins, asymmetric Diels-Alder cycloaddition, and enantioselective ring opening of epoxides.4,119... 

Also, pentadentate N302 SBs and their complexes have been reported.138,139 The spin-crossover phenomenon was investigated for Fem SB complexes derived from a pentadentate SB having a N302 donor set.140... 

Macrocyclic SB complexes have attracted much attention since the early 1980s, and several reviews covering this area of research have appeared.2 3,6 20-22 30 Hexaimino macrobicycles are also known.172-176... 

Schiff base (SB) complexes of the type, m-Mo02(SB)L (L = neutral donor), have attracted much attention and early work has been reviewed.394 These complexes generally exhibit distorted octahedral geometries with mer-Schiff base ligands. Complexes containing N02-donor ligands derived from salicylaldehyde, 3-methoxysalicylaldehyde, and 2-hydroxy-1-naphthaldehyde... 

The reactants as well as the intermediate alkyl species in this reaction have been characterised. Thus, the difficulty associated with interpreting NMR spectra of As and Sb complexes (arising from the unfavourable properties of the nuclei) has been partially circumvented by X-ray structural analysis. 

The fact that the [RhCl(CO)(SbPh3)2] complex shows comparable reactivity to 2 suggests similar electron density on the Rh-centre in both. However, the Sb complex shows a significant increased reactivity toward solvents, which is attributed to the smaller steric demand at the metal centre. ... 

When a Co Schiff-base (SB) complex in a nonaqueous solvent absorbs oxygen in the presence of a base (B), the following equilibria are established ... 

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