Germanium hydrides as an efficient hydrogen-storage material operated by an iron catalyst.

The use of metal hydrides such as NaBH 4 as hydrogen-storage materials has recently received substantial research attention on account of the worldwide demand for the development of efficient hydrogen-production, -storage, and -transportation systems. Here, we report the quantitative production of H 2 gas from a germanium hydride, Ph 2 GeH 2 , mediated by an iron catalyst at room temperature via dehydrogenative coupling, concomitant with the formation of (GePh 2 ) 5 . Of particular importance is that Ph 2 GeH 2 can be facilely recovered from (GePh 2 ) 5 by contact with 1 atm of H 2 or PhICl 2 /LiAlH 4 at 0 °C or 40 °C, respectively. A detailed reaction mechanism for the iron-catalyzed dehydrogenative coupling of Ph 2 GeH 2 is proposed based on the isolation of four intermediate iron species.