The Infrared Spectra of Alkylaluminum-Ether Complexes

Fifteen samples of alkylaluminum-ether complexes (alkyl=methyl or ethyl) have been prepared, and their infrared spectra have been measured in the 2000–350 cm−1 region. Most of the absorption bands in this region have been assigned. In the K Br prism region, the assignments of the absorption bands of the trimethylaluminum-dimethyl ether complex have been made on the assumption that this complex has the Cs symmetry only. The absorption bands of these complexes have been found to shift to lower frequencies in the C–O antisymmetric and symmetric streching vibrations in the order of trialkylaluminum-ether < dialkylaluminum halide-ether < alkylaluminum dihalide-ether complexes. The infrared spectra of five samples of ethylaluminum ethoxides have also been measured in the 2000 −350 cm−1 region.