Synthesis and Characterization of Five‐Coordinate Gallium and Indium Complexes Stabilized by Tridentate, Substituted Pyrrole Ligands

Abstract

Five‐coordinate gallium and indium complexes stabilized by tridentate, substituted pyrrole ligands have been synthesized and characterized. The reaction of MCl3 with 1 equiv. of Li[NC4H2(CH2NMe2)2‐2,5] in diethyl ether affords [{NC4H2(CH2NMe2)2‐2,5}MCl2] [M = Ga (1), In (2)] in high yield. Reaction of 1 with 2 equiv. of MeLi in diethyl ether at −78 °C followed by heating to reflux for 30 min affords the alkylated product [{NC4H2(CH2NMe2)2‐2,5}GaMe2] (3). Similarly, the reaction of 2 with 2 equiv. of MeLi or nBuLi affords the dialkylated complexes 4 and 5, respectively. Complex 2 is a strong Lewis acid which readily absorbs H2O forming [{[C4H2N(CH2NMe2)2‐2,5]InCl2}2(μ‐OH2)] (6). Complexes 3, 4, and 6 have been characterized by X‐ray crystallography. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Synthesis and characterization of new types of aluminum and gallium complexes stabilized by bifunctional ligands

“…The resonances assigned to the methyl substituents on gallium and aluminum are observed at −0.16 and −0.61 ppm for 1 and 2, respectively. For 1 this chemical shift is slightly downfield compared to those reported for similar gallium complexes with pyrrole ligands [{NC 4 H 2 (CH 2 NMe 2 ) 2 -2-5}GaMe 2 ] (δ −0.37 ppm) [15], and [{NC 4 H 3 (CH 2 NMe 2 )-2}GaMe 2 ] (δ −0.26 ppm) [16]. For 2 the chemical shift of the methyl substituents on aluminum is remarkably similar to the one observed for complex (tedta)AlMe 2 (tedta=tetraethyldiethylenetriamine) at −0.63 ppm [17].…”

Synthesis, Structures and Characterization of the Calcium Pyrrolates [Ca{(2‐(dimethylaminomethyl)pyrrolyl}2 donorn] (donor = THF and pyridine, n = 2; DME and TMEDA, n = 1) as Potential Precursors for Solid‐State Applications

“…Schematic drawing of the 2-DMAMP ligand Although first reported in the 1940Јs, [12] 2-DMAMP has received little attention as a ligand system. In fact, welcharacterized main group derivatives are limited to aluminum, [13] gallium and indium [14] in addition to some recently published mixed magnesium cyclopentadienide/amido derivatives. [15] Other metal complexes bearing DMAMP-type ligands include titanium, [16] tungsten, [16] zirconium, [17Ϫ19] vanadium, [19] thallium, [20] chromium, [19] molybdenum, [21] cobalt [19] and nickel.…”