Synthesis and characterisation of rhenium dithiocarbamate complexes. Crystal structures of [ReO{O(OH)C6H4}(S2CNEt2)(2)], [Re{PPh2(C6H4S-2)}(2)(S2CNEt2)]center dot Me2CO and [ReO{PPh(C6H4S-2)(2)}(S2CNEt2)]

The reaction of [Re2O3(S2CNEt2)(4)] with catechol in acetone yielded the dark orange complex [ReO{O(OH)C6H4}(S2CNEt2)(2)] 1. The crystal structure shows a distorted-octahedral geometry with the oxo group trans to the monodentate catecholate ligand. The Re-O (catechol) bond length is typical of a Re-O single bond and implies little trans influence of the oxo ligand. Reaction of [Re2O3(S2CNEt2)(4)] with 1,4-dihydroxybenzene yielded the red-brown dimer [{ReO(S2CNEt2)(2)}(2)(C6H4O2-1,4)] 2, in which the dianionic ligand bridges two rhenium centres. With 2-amino-4-methylphenol [ReO(OC6H3NH2-2-Me-4)(S2CNEt2)(2)] 3 was obtained containing the ligand co-ordinated in a monodentate mode. Reaction of [Re2O3(S2CNEt2)(4)] with dithiolate proligands such as ethane-1,2-dithiol yielded [ NEt2H2][ReOL2], L = C2H4S2-1,2 4, C6H4S2-1,2 5 or MeC6H3S2-3,4 6, where degradation of the dithiocarbamate ligands to form the diethylammonium counter ion occurs. Reaction of 1 with bidentate phosphines yielded green complexes of the general formula [Re(S2CNEt2)(2)L][BPh4], where L = Me2PCH2CH2PMe2 7 or Ph2PCH2CH2PPh2 8. These reactions can be contrasted to the inactivity of these phosphine ligands towards [Re2O3(S2CNEt2)(4)]. The reaction of [Re2O3(S2CNEt2)(4)] with the bidentate phosphinothiolate proligand PPh2(C6H4SH-2) in acetone at room temperature yielded the red-orange rhenium(III) complex [Re{PPh2(C6H4S-2)}(2)(S2CNEt2)]. Me2CO 9. The crystal structure revealed a distorted-octahedral geometry. The sulfur donors of the phosphinothiolate ligands adopt a cis configuration. Reaction of [Re2O3(S2CNEt2)(4)] with the tridentate phosphinothiolate proligand PPh(C6H4SH-2)(2) proceeded at room temperature to yield the red rhenium(v) complex[ReO{PPh(C6H6S-2)(2)}(S2CNEt2)] 10. Its crystal structure shows a distorted-octahedral geometry. Reaction of [Re2O3(S(2)CNEt2)(4)] with SiMe3Cl yielded the new rhenium(v) precursor [ReCl2(S2CNEt2)(2)][BPh4] 11 which permits investigation into rhenium dithiocarbamate chemistry without an oxo core.