title: A new class of binuclear gallium hydrides: synthesis and properties of [{GaCl(hpp)H}2] (hpp=1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidate).
abstract: Herein we report on the synthesis and characterization of the first representative of a new class of gallium hydrides, namely [{GaCl(hpp)H}2] (hpp=1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidate). Our X-ray diffraction data suggest the presence of weak H--H contacts between adjacent [{GaCl(hpp)H}2] molecules in the crystal. With the aid of quantum-chemical calculations, the pathway of its formation starting with the adduct H2ClGaNMe3 and the pyrimidine hppH were analyzed. [{GaCl(hpp)H}2] slowly decomposes at 25 degrees C, a process which presumably leads under H2 elimination to [{GaCl(hpp)}2]. Although we were not yet able to characterize [{GaCl(hpp)}2] experimentally, DFT calculations provide information about its likely structure. According to these calculations, the molecule features a Ga--Ga single bond.
authors.affiliation: Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, OX1 3QR, UK.
authors.forename: George
authors.initials: G
authors.lastname: Robinson
authors.forename: Christina Y
authors.initials: CY
authors.lastname: Tang
authors.forename: Ralf
authors.initials: R
authors.lastname: Köppe
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Cowley
authors.forename: Hans-Jörg
authors.initials: HJ
authors.lastname: Himmel