Copper complexes of 1,3-bis(2-pyridyl)-1-thiapropane (bpt) and pyridine-2(1H)-thione. Crystal structure of [{Cu(mu-O2CMe)(2)(bpt)}(2)] and metal-promoted cleavage of bpt

The reactivity of the asymmetric thioether 1,3-bis(2-pyridyl)-1-thiapropane [1-(2-pyridyl)-2-(2-pyridylsulfanyl)ethane] (bpt) with copper-(I) and -(II) starting materials has been investigated. Reaction with [Cu(NCMe)(4)]PF6 in MeCN gave a cluster formulated as [Cu-4(bpt)(6)][PF6](4), whilst reaction in tetrahydrofuran resulted in partial cleavage of bpt to give the mixed thionato-thioether complex [Cu-2(SC5H4N)(bpt)]PF6 [SC5H4NH = pyridine-2(1H)-thione]. Reaction with [Cu-2(mu-O2CMe)(4)] in MeOH gave the dimer [{Cu(mu-O2CMe)(2)-(bpt)}(2)], whose crystal structure shows that the bpt ligands are monodentate and co-ordinated via the N atom remote from the thioether. The compound bpt undergoes cleavage with other copper(II) salts such as Cu(BF4)(2), ultimately giving the hexameric copper(I) complex [Cu-6(SC5H4N)(6)]. The details of this reaction have been investigated. Reaction of SC5H4NH with Cu(NO3)(2) in the presence of HNO3 gave [Cu(NO3)(SC5H4NH)(2)], which in turn reacted progressively with PPh3 to give [Cu(NO3)(SC5H4NH)(2)(PPh3)] and the known complex [Cu(SC5H4NH)(2)(PPh3)(2)]NO3, whose crystal structure has been determined. Other complexes of SC5H4NH with copper(I) and a range of anions have been prepared, and the crystal structure of the dimer [Cu-2(SC5H4NH)(6)]-[MeC6H4SO3](2) is reported.