Indium complexes of 1,3-diphenyltriazene

Abstract

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.