Five co-ordinate

Where B = pyridine, piperidine or 1-methylimidazole, in methylene chloride solution, but under normal conditions rapid irreversible autoxidation takes place 232) leading to the formation of the well characterised 247, 248) fi-oxo product, (TPP)Fe(IlI)—0—Fe(III) (TPP) and since the rate of oxidation decreases 249, 250) with increasing excess of axial base, B, it follows 232, 251) that a five co-ordinate species, Fe(II) (Base)TPP, is probably involved as an intermediate which can then undergo a bimolecular termination reaction with Fe(II) (Base)02TPP, followed by autoxidation. Firstly 251),... 

The binuclear complex [I I(binap)Ir(/x-OMe)2(p-Cl)Irl I(binap)]Cl catalyzes the hydrogenation transfer from methanol to alkynes via the five co-ordinate intermediate lrHCl(OMe)(binap)].226... 

The preparation and characterization of five co-ordinate [(triphos)Ir(cat)]Z, H2cat = 9,10-phen-anthrenecatechol, 1,2-naphthalenecatecol, 3,5-di-tert-butylcatechol, 4-methylcatechol, 4-carboxy-catechol Et ester, tetrachlorocatechol, Z=BPh4, PF6, have been reported.244 All compounds... 

Measurements of the enthalpy of thermal decomposition of five co-ordinate perfluoro-olefin and -acetylene-iridium(I) complexes according to the equation... 

The extended structure of [Mn(ebbg)(OH2)] [N03]3 [50,51], is difficult to ascertain, owing to the five co-ordinate Mn(III) geometry and the non co-planarity of the cations and anions. Approximate sheet architectures can be discerned in planes parallel to (-1 3 1) and (1 -2 -2). The latter is shown in Fig. 25. In this view, the cations form dimeric pairs, which are linked through N03 anions and coordinated H20 molecules to form chains aligned in the [0 1 -1] direction. The... 

Nitriloacetic acid reacts with vanadium-(m). -(iv), or -(v) oxides to form oxovanadatranetrionic acid (38). The crystal structure of [VO(CjQHgNO)2] (CjgHgNOH = 2-methyl-8-quinolinol) has shown that the vanadium atom has a five-co-ordinate trigonal-bipyramidal environment, with three oxygen atoms in the equatorial plane and the two nitrogen atoms of the bidentate ligand in the apical positions. The optimum conditions for the formation of a 1 2 2 vanadium(iv)-morin-4-aminoantipyrine system have been described as pH 5, a tenfold excess of morin (39), and a 3300-fold excess of 4-amino-antipyrine. ... 

N-, P-, As-, and Sh-donor Ligands. [Cr(CO) (bipy)] has been reduced by sodium in THF. Electronic and e.s.r. spectra of the resulting complex suggest that it involves co-ordination of the uni-negative ion of bipy. The complex loses CO to afford either a five-co-ordinate complex or a dimeric species. ... 

Molecules of CrCl3,2Me3N are five-co-ordinated with a basically trigonal-bipyramidal geometry. The average bond lengths are Cr—Cl = 223.8 (5) and Cr—N = 215 pm two Cl—Cr—Cl angles are 124.3 (I) and the other is 111.4 (2)°, The distortion from idealized symmetry may be attributed to electronic effects since in symmetry there will be one electron in an e MO. ... 

The five-co-ordin ite complexes [Fe(cdpp).X]X (.X = Cl or Br cdpp = 8-quinoldiphenylphosphine) have been prepared. 

The potentially terdentate ligand, thiodiethanol (88), forms 1 1 complexes and 1 2 complexes with C0CI2. The former are five-co-ordinate and the latter octahedral. 1 1 Complexes of Co and diethylenetrithioacetic acid, ethylene-dithiodiacetic acid, and ethylidenetetrathiotetra-acetic acid have all been reported." " Potassium monothiobenzoate reacts with an equimolar quantity of CoSO in aqueous solution to yield green crystals of the pseudo-tetrahedral dinuclear complex [Co2(SOCPh)4 ], which contains both bidentate and bridging thiobenzoate ligands. ... 

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