The coordination chemistry of small sulfur-containing molecules: a personal perspective

The sulfur oxides SO, SO2 and SO3, and thioformaldehyde H2C=S and its oxides H2C=SO and H2C=SO2 form stable coordination compounds with a range of transition metals. The complexes have a rich chemistry which differs markedly from that of the free ligands. Typical reactions involve electrophilic additions, nucleophilic additions and cycloadditions. The complexes can be used as synthons to incorporate these small molecules as building blocks into larger structures.