Transmetalation reactions of sterically encumbered gallium and indium halides with tetrahydrometalates. Synthesis and structure of a base-free monomeric aluminum hydride

Article abstract of DOI:10.1021/om00005a067

The reaction of (Ar*)₂GaCl or (Ar*)₂InCl (Ar* = 2,4,6-t-Bu₃C₆H₂) with LiAlH₄ resulted in transmetalation and formation of (Ar*)₂AlH (6), the first example of a structurally authenticated monomeric base-free aluminum hydride. An X-ray crystallographic study revealed that the monomeric nature of the new hydride is due to the shielding of the Al-H moiety by o-t-Bu groups of the aryl ligands. Crystal data for 6: space group P2₁/c, a = 10.024(2) ?, b = 29.745(4) ?, c = 11.459(1) ?, β = 94.87(1)°, V = 3404(2) ?³, Z = 4. The X-ray crystal structure of (Ar*)₂InCl (5) has also been determined. Crystal data for 5: space group P2₁/c, a = 10.328(2) ?, b = 22.924(2) ?, c = 16.091(1) ?, β = 107.34(1)°, V = 3636.6(8) ?³, Z = 4.