title: Synthesis of a stable adduct of dialane(4) (Al2H4) via hydrogenation of a magnesium(I) dimer.
abstract: The desorption of dihydrogen from magnesium(II) hydride, MgH2 (containing 7.6 wt% H), is reversible. MgH2 therefore holds promise as a hydrogen storage material in devices powered by fuel cells. We believed that dimeric magnesium(I) dimers (LMgMgL, L=β-diketiminate) could find use as soluble models to aid the study of the mechanisms and/or kinetics of the hydrogenation of magnesium and its alloys. Here, we show that LMgMgL can be readily hydrogenated to yield LMg(µ-H)2MgL by treatment with aluminium(III) hydride complexes. In one case, hydrogenation was reversed by treating LMg(µ-H)2MgL with potassium metal. The hydrogenation by-products are the first thermally stable, neutral aluminium(II) hydride complexes to be produced, one of which, [{(IPr)(H)2Al}2] (IPr=:C[{(C6H3-i-Pr(2)-2,6)NCH}2]), is an N-heterocyclic carbene adduct of the elusive parent dialane4 (Al2H4). A computational analysis of this compound is presented.
authors.affiliation: School of Chemistry, Monash University, Melbourne, PO Box 23, Victoria, 3800, Australia.
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Bonyhady
authors.forename: David
authors.initials: D
authors.lastname: Collis
authors.forename: Gernot
authors.initials: G
authors.lastname: Frenking
authors.forename: Nicole
authors.initials: N
authors.lastname: Holzmann
authors.forename: Cameron
authors.initials: C
authors.lastname: Jones
authors.forename: Andreas
authors.initials: A
authors.lastname: Stasch
mesh_terms: D017607:Aluminum Compounds / Q000737:chemistry*; D019281:Dimerization; D006859:Hydrogen / Q000737:chemistry*; D008274:Magnesium / Q000737:chemistry*
chemical_list: D017607:Aluminum Compounds; D006859:Hydrogen; D008274:Magnesium