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The reaction of equimolar quantities of trans -[ReOCl 3 (PPh 3 ) 2 ] and 8-hydroxyquinoline (Hhqn) in benzene led to the isolation of the six-coordinate complex [ReOCl 2 (hqn)(PPh 3 )] ( 1 ). With 2-pyridine-ethanol (Hhep) the compound [ReOCl 2 (hep)(PPh 3 )] ( 2 ) was obtained. Both hqn and hep ligands act as monoanionic bidentate N , O -donor chelates. Although the two complexes are very similar, there are some significant differences in certain bond distances and angles in them. Both complexes contain the nearly linear trans O=Re–O axis, with this angle equal to 160.9(2)° and 167.8(1)° in 1 and 2 , respectively. [ABSTRACT FROM AUTHOR]

Reactions of trans -[ReOCl 3 (PPh 3 ) 2 ] and trans -[ReO(OEt)I 2 (PPh 3 ) 2 ] with 2-aminophenol (H 2 ap) in acetonitrile led to the formation of cis -[ReOCl 2 (Hap)(PPh 3 )] (1) and trans -[Re(ap)(Hap)I(PPh 3 ) 2 ]I (2), respectively. The X-ray crystal structures show that Hap is coordinated as a bidentate chelate via the neutral amino nitrogen and deprotonated phenolate oxygen, and ap is coordinated as a monodentate through the imido nitrogen. The complexes have been characterized by IR spectroscopy, NMR spectrometry and X-ray crystallography. The bite angle of the Hap chelate is 76.9(1)° and 76.0(1)° in 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

The neutral, mononuclear complex [ReO(mta) 2 Cl] (1) [Hmta  =  2-(methylmercapto)aniline] was prepared by reaction of trans -[ReOCl 3 (PPh 3 ) 2 ] with a twofold molar excess of Hmta in methanol. The oxo-bridged dimer (μ-O)[ReO(mta) 2 ] 2 (2) was synthesized by reacting [ReOCl 3 (PPh 3 ) 2 ] with a twofold excess of Hmta in a 9  :  1 acetone/water mixture. The compounds were characterized by spectroscopy and complex 1 also by X-ray crystallography. Complex 1 has a distorted octahedral geometry with the chloride coordinated trans to the oxo group, and with the chelating ligands in the equatorial plane in a cis-N cis-S configuration. [ABSTRACT FROM AUTHOR]

The cationic complex [ReO(ahp)2(PPh3]+ was isolated as the chloride salt from the reaction of trans- [ReOCl3(PPh3)] and 2-amino-3-hydroxypyridine (Hahp) in ethanol. Coordination of the chelates only occurs through the amino nitrogen and the phenolate oxygen of ahp-. The X-ray crystal structure shows a distorted octahedral geometry, in which a phenolate oxygen coordinated trans to the oxo group and the rhenium atom is displaced by 0.2520(1) Å out of the mean equatorial plane towards the oxo oxygen. [ABSTRACT FROM AUTHOR]

The complex [ReO(Hamb)(H2amb)(PPh3)](1) was prepared by the reaction of csi-[ReO2I(PPh3)2] with two equivalents of 2-amino-3-methylbenzoic acid (H3amb) in toluene under reflux conditions. Crystallographic data show that 1 contains the coordinated amidobenzoate chelate (Hamb) and symmetrically chelating carboxylate ion (H2amb) in a pseudo-octahedral geometry. [ABSTRACT FROM AUTHOR]

The reaction of a twofold molar excess of 2-aminothiophenol (H2L) with trans-[ReOCl3(PPh3)2] in benzene led to the isolation of the oxo-free rhenium(V) complex [ReCl(PPh3)L2] (1), IR, ¹H NMR and X-ray crystallographic results indicate that the ligands L coordinate in a dianionic form to the metal and that the complex has the unusual skew-trapezoidal bipyramidal geometry. The ligands L have an average bite angle of 78,8(1)°, with average Re-N and Re-S bond lengths equal to 1,978(5) and 2,297(1) A, respectively. [ABSTRACT FROM AUTHOR]

The complex [ReOI 2 (ame)(PPh 3 )] (Hame=2-(2-aminophenyl)ethanol) was prepared from trans -[ReOI 2 (OEt) (PPh 3 ) 2 ] and Hame in benzene. It contains an unusually long Re=O bond (1.717(5) Å) and a large trans O=Re-O (ethanolate) bond angle of 171.4(2)°. [ABSTRACT FROM AUTHOR]

The complex [Re(ddcat) 3 ] (H 2 ddcat = 3,5-di- tert -butylcatechol) was prepared by the reaction of either cis -[Re V O 2 I(PPh 3 ) 2 ] or ( n -Bu 4 N)[Re V OCl 4 ] with H 2 ddcat in toluene in air. X-ray structure determination of the product unequivocally illustrates that the bidentate chelates are in the catecholato rather than the semiquinone form and that the metal has a formal oxidation state of +VI. [ABSTRACT FROM AUTHOR]

The reaction of a twofold molar excess of 2-amino-3-methylbenzoic acid (H 3 amb) with cis -[ReO 2 I(PPh 3 ) 2 ] in ethanol led to the isolation and characterization of the six-coordinate [Re(amb)(OEt)I(PPh 3 ) 2 ] ( 1 ). The X-ray crystal structure of 1 illustrates that the trianionic ligand amb acts as a bidentate chelate via the doubly deprotonated amino nitrogen, which is present in 1 as an imide, and the deprotonated acetoxy oxygen. The Re=N bond length is 1.751(3) Å, and the Re=N-C angle [143.6(3)°] deviates considerably from linearity. [ABSTRACT FROM AUTHOR]

Reactions of trans-[ReO[sub 2](py)[sub 4]Cl] and cis-lReO[sub 2]I(PPh[sub 3])[sub 2]] with 2,3-diaminophenol (H[sub2]dab-OH) and 1,2-diaminobcnzcne (H[sub 2]dab), respectively, in ethanol under aerobic conditions led to the corresponding isolation of [Re(sbqdi-OH)[sub 3]]C1 (1) and [Re(sbqdi)[sub 3]]) (2). Crystallographic data show that the ligand sbqdi represents the monoanionic N,N-coordinatcd π-radical form of the 1,2-benzosemiquinone diimine of H[sub 2]dab. The ligands in Complex 1 clearly show semiquinoid character; e.g., the two C N and two Re N bondlengths differ considerably. In 2, the phenyl rings display typical quinoid distortions with two localized double bonds, and the C N bondlengths are short, approaching double bonds. Rhenium is formally in the +IV oxidation state. [ABSTRACT FROM AUTHOR]