title: Bipodal acylthiourea ligands as building blocks for Bi-, tetra-, and polynuclear oxorhenium(V) complexes.
abstract: Reactions of (NBu4)[ReOCl4] and 3,3,3',3'-tetraalkyl-1,1'-isophthaloylbis(thioureas), H2phth(R2tu)2 where R = Et, i-Bu, in hot MeOH with the addition of Et3N give red products of the composition [ReO(OMe){phth(R2tu)2}]2 (8a, R = Et; 8b, R = i-Bu). X-ray structures of 8 reveal symmetric binuclear complexes containing two almost coplanar organic ligands, each of which coordinates to two rhenium centers via the two bidentate-O,S moieties. The octahedral coordination spheres of the rhenium atoms are completed by each one oxo and one methoxido ligand which are directed perpendicular to the plane defined by the {phth(R2tu)2}(2-) ligands. While in 8a, both methoxido ligands point to the same side of the described plane and form a syn isomer, the MeO(-) ligands in 8b are located at opposite sides and form an anti isomer. Studies in solution show that there exists a reversible equilibrium between the anti and syn isomers. Dimerization/condensation of complexes 8 with the formation of tetranuclear complexes of the composition [{ReO{phth(R2tu)2}}2O]2 (9) and/or polynuclear species is observed in solutions, which do not contain MeOH.
authors.affiliation: Department of Chemistry, Hanoi University of Science, 19 Le Thanh Tong, Hanoi, Vietnam.
authors.forename: Hung Huy
authors.initials: HH
authors.lastname: Nguyen
authors.forename: Pham Chien
authors.initials: PC
authors.lastname: Thang
authors.forename: Axel
authors.initials: A
authors.lastname: Rodenstein
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kirmse
authors.forename: Ulrich
authors.initials: U
authors.lastname: Abram
mesh_terms: D007202:Indicators and Reagents; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D012211:Rhenium / Q000737:chemistry*; D012996:Solutions; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D017550:Spectroscopy, Fourier Transform Infrared; D013890:Thiourea / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D007202:Indicators and Reagents; D008024:Ligands; D012996:Solutions; C015428:perrhenate; D012211:Rhenium; D013890:Thiourea