Synthesis, structure and reactions of the first tellurium-containing macrocyclic Schiff base

Abstract

The condensation of bis(2-formylphenyl) telluride 1 with ethane-1,2-diamine yielded the novel macrocyclic tellurium ligand 2 via metal-free dimerisation. Crystals of 2 are triclinic, space group <P(1)over bar> with a = 7.956(3), b = 9.885(2), c = 1.068(2) Angstrom, Z = 1. Hydrogenation of macrocycle 2 provided the corresponding saturated tetraazamacrocycle 3, protonation of which with HBr afforded 4. The co-ordination chemistry of 2 has been studied with 'soft' metal ions such as palladium(II) and mercury(II). N,N'-Bis[(2-chloroteIluranyl)benzylidene]ethane-1,2-diamine has also been characterised by an X-ray diffraction study, with triclinic space group <P(1)over bar>, a = 7.71(1), b = 7.90(1), c = 8.52(1) Angstrom and Z = 1.