John T. Leman

Synthesis of 1,3-diphenyltriazenide complexes of aluminium, gallium and indium: crystal structure of tris(1,3-diphenyltriazenido) aluminium (III)

Abstract The reaction of AlMe 3 with 1,3-diphenyltriazene [Hdpt] in toluene gives Al(dpt) 3 , even when AlMe 3 is in large excess. The monomeric structure has been established by X-ray diffraction. Crystals of Al(dpt) 3 are monoclinic, space group C 2/ c with a = 20.587(3), b = 16.005(3), c = 13.236(3) A and β = 119.172(12)°, Z = 4, R = 0.067 and R w = 0.083. The aluminium(III) is coordinated by three chelating triazenido ligands to give a trigonally distorted octahedral geometry. The gallium and indium analogues are also reported.

REACTIVITY OF DECAMETHYLSAMAROCENES WITH TRIALKYLALUMINUM REAGENTS INCLUDING THE STRUCTURE OF A BRIDGED ISOBUTYLALUMINUM COMPLEX, (C5Me5)2Sm[(μ-CH2CHMe2)2AI(CH2CHMe2)2]

Abs t rac t . (C5Me5)2Sm(THF)2 and (CsMes^Sm react with AI(CH2CHMe2)3 to form several products including the unusual isobutyl-bridged Sm-AI heterobimetall ic species (C5Me5)2Sm[(pCH2CHMe2)2AI(CH2CHMe2)2]. 1 No reaction is observed between AI(CMe3 )3 and (C5Me5 )2Sm, but (C5Me5)2Sm(THF)2 reacts to lose THF and form AI(CMe3)3(THF) and (C5Me5)2Sm. No fur ther reaction occurs between AI(CMe3)3(THF) and (C5Me5)2Sm.

Indium complexes of 1,3-diphenyltriazene

The reaction of InCl3 with 1,3-diphenyltriazene (Hdpt) in the presences of NEt3 gives the six-co-ordinate indium complex [NHEt3][InCl2(dpt)2]1a. The interaction of 1a with [NEt4]Cl and [N(PPh3)2]Cl allows for the isolation of the appropriate salts, [NEt4][InCl2(dpt)2]1b and [N(PPh3)2][InCl2(dpt)2]1c. Reaction of Lewis bases, L, with 1a yields [InCl2(dpt)L2], L = pyridine 2, 3,5-dimethylpyridine 3, PEt34, L2= 2,2′-bipyridine 5, 1,10-phenanthroline 6, Me2PCH2CH2PMe27 or Et2PCH2CH2PEt28. The mechanism for these reactions is discussed. No reaction is observed between 1b and 3,5-dimethylpyridine. The X-ray structures of 1a, 3, 4 and 5 have been determined. Compounds 2–4 are readily soluble in aromatic hydrocarbon solvents, while 5–8 are insoluble as a consequence of the presence of a supramolecular architecture involving dipolar In–Cl ⋯ N interactions in the solid state. All new compounds have been characterised by 1H, 13C-{1H} and 31P-{1H} NMR and IR spectroscopy.