Darstellung, Struktur und einige Reaktionen von Tris(dimethylamino)gallan / Preparation, Structure and Some Reactions of Trisdimethylaminogallane

Abstract

The aminogallanes Ga[N(CH3)2]3 (1), ClGa[N(CH3)2]2 (2) and Ga[N(Si(CH3)3)2]3 (3) are prepared by reacting GaCl3 with LiN(CH3)2 and NaN[Si(CH3)3]2, respectively. Excess LiN(CH3)2 leads to LiGa[N(CH3)4] which reacts with GaCl3 to yield 1. CS2 inserts into all Ga—N bonds of 1 yielding monomeric Ga[S2CN(CH3)3)2]3 (4). 1 dimerizes via dimethylamino bridges. In contrast, 1H. NMR spectra indicate group exchange for dimeric 2. Assoziation of 3 is prevented due to steric hindrance. The gallium atom in 4 exhibits hexacoordination, and there is evidence for the binding of the (CH3)2NCS2 groups through S atoms only.