A new class of mixed aza-thioether crown containing a 1,10-phenanthroline sub-unit

The new aza-thioether crowns [15]ane(phen N-2)S-3 and [19]ane(phen N-2)S-4 have been synthesised. Their complexation with nickel(II) salts afforded a range of octahedral complexes. The single crystal structures of [Ni{[15]ane(phen N-5)S-3)}(NCMe)][BF4](2), [NiCl{[15]ane(phen N-2)S-3}]BF4 . dmf(dmf = dimethylformamide) and [Nil{[15]ane(phen N-2)S-3}][I-3] have been determined and confirm N2S3 donation of the aza-thioether crown in a folded conformation to Ni-II with the sixth co-ordination site taken up by MeCN, Cl- and I- respectively. The complex [Ni2Cl2{[19]ane(phen N-2)S-4}(2)][BF4](2) . 3MeNO(2) shows a dichloro-bridged binuclear structure with the aza-thioether crown bound via only two S- and two N-donors, with two thioether S-donors unbound. A dichloro-bridged binuclear structure was found also for [Ni2Cl2{[12]ane-(py N)S-3}(2)][BF4](2) . 1.5MeNO(2). The redox properties of [Ni{[15]ane(phen N-2)S-3}(NCMe)][BF4](2) in MeCN have been examined.