When solid-state rhenium sulfide clusters with an octahedral metal framework are treated in a hydrogen stream above 250 degrees C, a catalytic activity for dehydrogenation of cyclohexanone to yield 2-cyclohexen-1-one and phenol develops. Dehydrogenation of cyclohexanol to cyclohexanone and hydrogenation of phenylacetylene to styrene also proceed. This catalytic behavior is the same as that of the platinum group metals. The catalytic activities are attributable to the partial loss of the sulfur ligands.