TECHNETIUM AND RHENIUM COMPLEXES WITH THIOETHER LIGANDS .4. SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF BINUCLEAR OXORHENIUM(V) COMPLEXES WITH BIDENTATE THIOETHER COORDINATION

摘要

Binuclear oxorhenium(V) complexes, [ReO(''S-2'')Cl-2]O-2, have been prepared by reduction of ReO4- with SnCl2 in strongly acidic solution and in the presence of aliphatic thioethers of the general formula R-CH2CH2-S-CH2CH2-S-CH2CH2-R' (''S-2''; R, R' = H, Et; R = S-Bu, R' = Et; R = O-Et, R' = H; R, R' = O-Et). Alternatively the compounds can be obtained by ligand exchange reactions starting from [ReOCl4](-) in methanolic solution. A representative derived from 5,8-dithiadodecane (R,R' = Et) has been studied by X-ray diffraction. The complex consists of two independent [ReO(''S-2'')Cl-2] units bridged by an oxygen atom. Each rhenium atom is centred in a distorted octahedron with the equatorial plane formed by the S2Cl2 donor set. The sulphur and chlorine atoms of the units are in the anti position with respect to the bridging oxygen. [References: 12]