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Herein we report the zwitterionic pentagonal bipyramidal oxidorhenium(V) complex trans-[ReOI2(bpp)] where bpp is (1E,3E)-1,3-bis(pyrimidin-2-ylimino)propan-2-ide anion. The complex trans-[ReOI2(bpp)] was unusually formed from the reaction of trans-[ReOI2(OEt)(PPh3)3] with 2-aminopyrimidine in propan-2-ol in the presence of triethylamine (Et3N). The anionic ligand bpp was formed by oxidorhenium(V)-catalysed dehydroxylation of propane-2-ol followed by condensation with 2-aminopyrimidine, and coordinates to the [ReO]3+ core as tetradentate N-donor chelate. A few numbers of pentagonal bipyramidal complexes are known for oxidorhenium(V), and the complex trans-[ReOI2(bpp)] is another example. The complex was analyzed by 1H NMR, IR, UV-visible and single crystal X-ray crystallography. In addition, density functional theory (DFT) was also studied. [ABSTRACT FROM AUTHOR]

The reaction of trans -[ReOI 2 (OEt)(PPh 3 ) 2 ] with dithizone in ethanol led to the isolation of the complex salt [ReO(dz) 2 ][ReO(HL) 2 ] ( 1 ), which contains the ionic oxorhenium(V) complexes [ReO(dz) 2 ] - and [ReO(HL) 2 ] + . The new NS-donor ligand triphenylphosphazeno- N -phenylmethanethiohydrazide HL was formed by the replacement of the Ph-N group on the azoic side of dithizone by the substituted triphenylphosphine of the starting material, and is a rare example of the in situ formation of this type of ligand. The salt ( n -Bu 4 N)[ReO(dz) 2 ] ( 2 ) was isolated from the reaction of ( n -Bu 4 N)[ReOCl 4 ] with H 2 dz in ethanol. Compounds 1 and 2 were characterized by elemental analysis, FTIR, proton NMR and single crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

The rhenium(I) compound fac-[Re(CO)3(daa)].Hpab.H2O (Hpab = N,N'-(1,2-phenylene)bis(2′-aminobenzamide); Hdaa = 2- amino-N-(2-aminophenyl)benzamide) was synthesized from the reaction of [Re(CO)5Br] with two equivalent of Hpab in toluene. The monoanionic tridentate ligand daa was formed by the rhenium-mediated cleavage of an amido N-C bond of the potentially tetradentate ligand Hpab. The compound was characterized by IR spectroscopy and X-ray crystallography, and daa is coordinated as a diaminoamide via three nitrogen-donor atoms. [ABSTRACT FROM AUTHOR]

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]

The reaction of a two-fold molar excess of the potential N,O-donor ligand 2-(hydroxymethyl)-l-methylimidazole (Hmi) with trans-[ReOCl[sub 3](PPh[sub 3])[sub 2]] led to the isolation of cis-[ReOCl[sub 2](mi)(PPh[sub 3])]. An X-ray structure determination indicated that the complex has distorted octahedral geometry, and that mi coordinates as a bidentate with the alcoholate oxygen trans to the oxo group. A similar reaction with 2-(1-ethyloxomethyl)1-methylimidazole (eomi), the ethyl substituted analogue of Hmi, led to the formation of the oxo-bridged dinuclear complex [(μ-O){ReOCl[sub 2](comi)[sub 2]}[sub 2]]. The ligand comi coordinates as a monodentate ria the imidazole nitrogen, with the "hard" ether oxygen uncoordinated. An X-ray crystal structure indicates that the chlorides are trans to each other in the ReN[sub 2]CI[sub 2] planes, which are orthogonal to the O=Re O Re=O backbone. [ABSTRACT FROM AUTHOR]

Monooxo complexes of rhenium(V) with 2-aminophenol and some of its derivatives (H 2 nod), containing the N , O donor-atom set, have been synthesized. Square-pyramidal complexes [ReO(nod) 2 ] - were isolated by reaction with ( n -Bu 4 N) [ReOCl 4 ] in ethanol. In benzene the neutral species [ReOCL(Hnod) 2 ] were obtained. In the presence of hydrochloric acid in ethanol, the anionic complexes ( n -Bu 4 N) [ReOCl 3 (Hnod)] were produced. Trans -[ReOCl 3 (PPh 3 ) 2 ] was also reacted with some of the H 2 nod ligands to yield [ReOCL 2 (Hnod)(PPh 3 ]. The crystal structure of [ReOCl 2 (Hmap)(PPh 3 )] (H 2 map = 2-aminobenzylalcohol) was determined; crystals are monoclinic, P 2 1 / n , with a = 15.065(6), b = 11.253(7), c = 15.850(7) Å, β = 94.27(4)°, U = 2680(2) Å 3 and Z = 4. The structure was solved by the Patterson method and refined by full-matrix least-squares techniques to R = 0.042. The monoanionic Hmap - ligand is coordinated as a bidentate through a neutral amino nitrogen and an anionic alcoholate oxygen atom, with the latter trans to the oxo group. [ABSTRACT FROM AUTHOR]