- Experimental and theoretical studies on some energetic functionalized trimethylamine derivatives
-
The synthesis and structural properties (from X-ray diffraction or B3LYP/6-31G(d) calculations) of three energetic compounds derived from tris(chloromethyl)amine and of tris(chloromethyl)amine itself were investigated and compared to those of compounds with similar structures. The compounds have almost planar NC3 units at their amine center, and the substituents bound to the CH2 groups tend to be reactive towards further substitution. Multiple hyperconjugation was used to explain these observations.
- Klapoetke, Thomas M.,Krumm, Burkhard,Scherr, Matthias,Xaver Steemann,Banert, Klaus,Joo, Young-Hyuk
-
-
Read Online
- Synthesis of azidochloromethane and azidobromomethane
-
By treatment of tris(azidomethyl)amine with dry hydrogen halide, azidochloromethane and azidobromomethane were prepared. The former product, which is more stable than the latter, was isolated as a colorless liquid. The desired azidohalomethanes are intermediates in the nucleophilic substitution of dihalomethanes to generate diazidomethane but could not be detected in this transformation.
- Banert, Klaus,Joo, Young-Hyuk,Rüffer, Tobias,Walfort, Bernhard,Lang, Heinrich
-
body text
p. 2880 - 2882
(2010/06/14)
-
- Nonadditivity of secondary deuterium isotope effects on basicity of trimethylamine
-
Secondary deuterium isotope effects (IEs) on basicities of isotopologues of trimethylamine have been accurately measured by an NMR titration method applicable to a mixture. Deuteration definitely increases the basicity, by ~0.021 in the ΔpK per D. The IE is attributed to the lowering of the CH stretching frequency and zero-point energy by delocalization of the nitrogen lone pair into the C-H antibonding orbital. Because this depends on the dihedral angle between the lone pair and the C-H, a further consequence is a preference for conformations with H antiperiplanar to the lone pair and D gauche. This leads to a predicted nonadditivity of IEs, which is confirmed experimentally. It is found that the decrease in basicity, per deuterium, increases with the number of deuteriums. The nonadditivity of IEs is a violation of the widely assumed Rule of the Geometric Mean.
- Perrin, Charles L.,Dong, Yanmei
-
supporting information; experimental part
p. 11143 - 11148
(2009/02/05)
-