Abstract
Bis(phenanthro1ine) and bis(bipyridine)ruthenium(~~) chelates have been prepared by the pyrolysis, at 300°C, of phenanthrolinium tetrachlorophenanthrolineruthenate(III) and bipyridinium tetrachlorobipyridineruthenate(III). In the complexes [RuB2Cl2] the chelating base molecules are firmly bound but the chlorine atoms are replaceable by a variety of ligands such as water, pyridine, or acetylacetone. The complexes are spin-paired and show no tendency to disproportionation to the tris complexes, under normal experimental conditions.