New chain clusters of rhenium connected by Re–H–Re interactions: A low-temperature NMR investigation

The addition of small amounts of hydrido-carbonyl rhenates or simply of H− to the “ethylene-like” complex [Re2(μ-H)2(CO)8] triggers an oligomerization process, that affords hydrogen-rich chain clusters made of Re(CO)4 units joined by Re(μ-H)Re interactions. Each oligomerization step is reversible, and the equilibria favour the longer oligomers at the lowest temperatures, where nuclearities up to 10 are reached.