Synthesis of Molecular Gallium Hydrides by Means of Low-Temperature Catalytic Dehydrogenation



Low-temperature catalytic dehydrogenation of H3Ga·NMe3 and a bicyclic guanidine [1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine (hppH) or 1,5,7-triazabicyclo[4.3.0]non-6-ene (Htbn)] led to temperature-sensitive gallium hydrides H3Ga(tbn)·Htbn and [H2Ga(μ-hpp)]2. Both hydrides, which are stable only at low temperatures, were structurally characterized. A possible pathway and the role of the catalyst are discussed on the basis of NMR spectroscopic experiments and quantum chemical calculations.