Collect. Czech. Chem. Commun. 1981, 46, 2600-2612

Donor-acceptor complexes of trimethylamine with selenium trioxide, sulphur trioxide, and sulphur dioxide

Jiří Toužín and Petr Bauer

Department of Inorganic Chemistry, Purkyně University, 611 37 Brno


Study of reaction course of trimethylamine with selenium trioxide by conductometric titration and vibration spectra of the products proved that the reaction produces, besides the known donor-acceptor complex (CH3)3N.SeO3, also the adduct (CH3)3N.S2O6 similar to that formed in the system pyridine-selenium trioxide. Although the latter adduct could not be isolated in pure state, the results obtained indicate its structural analogy to the compound C5H5N.Se2O6. In preparation of the both DA complexes of selenium trioxide and trimethylamine the adduct (CH3)3N.SO2 is an important intermediate whose vibration spectra were measured and interpreted, too. Comparison and characterization of bonding relations in the DA complexes (CH3)3N.SeO3 and (CH3)3N.SO3 were carried out on the basis of results of normal coordinate analysis.