Ab initio studies of structural features not easily amenable to experiment. 58. Comparison of the molecular structures of some di-tertiarybutyl compounds of type [(CH3)3C]2X

by Siam, Khamis S.; Ewbank, John David; Schäfer, Lothar; Van Alsenoy, Christian

The molecular structures of a series of di-tertiarybutyl compounds of type [(CH3)3-C]2X, with X=NH, O, SiH2, PH, and S, were determined by ab initio gradient geometry refinements on the 4-21G (first row elements) and 3-3-21G* (second row elements) levels. Together with results previously obtained for di-t-butyl methane, the structural data allow describing a number of consistent trends in the homologous systems involving the C-X bonds, C-X-C angles, and internal t-butyl parameters. Important details of the geometry calculated for di-t-butyl amine are not in agreement with a previous electron diffraction study of the compound which was obtained subject to simplifying assumptions needed for data analysis. Due to different interactions with the X-H group, the two t-butyl groups are found to be non-equivalent in the NH and PH systems.

Journal
Journal of Molecular Structure-Theochem
Volume
153
Issue
1-2
Year
1987
Start Page
165
ISBN/ISSN
2210-2728; 0166-1280
DOI
10.1016/0166-1280(87)85014-5