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 2via metal-free dimerisation. Crystals of 2 are triclinic, space group P with a= 7.956(3), b= 9.885(2), c= 10.068(2)Å, 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-chlorotelluranyl)benzylidene]ethane-1,2-diamine has also been characterised by an X-ray diffraction study, with triclinic space group P, a= 7.71(1), b= 7.90(1), c= 8.52(1)Å and Z= 1.