Technetium and Rhenium Complexes with Thioether Ligands, 5. Synthesis and Structural Characterization of Neutral Oxorhenium(V) Complexes with Tridentate Dithioethers

Abstract

AbstractNeutral oxorhenium(V) complexes of the general formula ReO(L)Cl2 are obtained by reaction of [ReO4]− or [ReOCl4]− with functionalized dithiaalcohols (L) containing the donor atom sequences S, S, O− and S, O−, S. Ligand exchange reaction of [ReOCl4]− with HO(CH2)2S(CH2)2S(CH2)2O (R = H, Et ) leads to the formation of ReOCl2[O(CH2)2S(CH2)2‐S(CH2)2OEt] (1b). Reduction of [ReO4]− with a 1:1 mixture of concentrated HCl and glacial acetic acid in the presence of nBuSCH2‐ CH(OH)CH2S‐nBu yield ReOCl2[OCH(CH2S–nBu)2) (4). X‐ray structure analysis of 1a, 1b and 4 shows distorted octahedral coordination with the chlorine and sulfur atoms in the equatorial plane. The oxygen of the hydroxyl group coordinates in a trans position with respect to the ReO core. 1a reacts with an excess of acetyl chloride in an unexpected way, resulting in cleavage of the trans Re–O bond and acylation of both of the hydroxyl groups to form the μ‐oxo bridged complex [ReOCl2{CH3COO{CH2)2S(CH2)2PPC‐CH3}}2O (3).