Jeremy M. Rawson and John J. Longridge
Poly(sulfur nitride), [SN]x, was the first example of a polymeric metal, and the discovery of its superconducting properties in 1973 fuelled a generation of research into the areas of sulfur–nitrogen chemistry and molecular conductors. The synthesis, structure and properties of [SN]x now form part of many undergraduate courses and it is an often cited textbook example. Now, in the 1990s, small fragments of [SN]x may prove useful as molecular wires in the development of nanoscale technology. Although the preparations of many thiazyl chains can be carried out in a rational high-yielding manner, it is the diverse reaction chemistry, which often involves unexpected changes in the chain size, which provides one of the most rewarding and stimulating aspects of this area.