TY  - JOUR
A1  - Baranac-Stojanovic, Marija
A1  - Keinpeter, Erich
T1  - Quantification of the aromaticity of 2-Alkylidenethiazolines subjected to push-pull activity
JF  - The journal of organic chemistry
N2  - Through-space NMR shieldings (TSNMRSs) of a series of 2-alkylidenethiazolines subjected to push-pull activity have been calculated by the GIAO method employing the nucleus-independent chemical shift (NICS) concept and visualized as iso-chemical-shielding surfaces (ICSSs). The ICSSs were applied to quantify and visualize the degree of aromaticity of the studied compounds, which has been shown to be in excellent correlation with the push-pull behavior, quantified by the quotient (pi*/pi) method. Dissection of the absolute magnetic shielding values into individual contributions of bonds and lone pairs by the natural chemical shielding-natural bond orbital (NCS-NBO) analysis has revealed unexpected details.
Y1  - 2011
U6  - https://doi.org/10.1021/jo200294f
SN  - 0022-3263
VL  - 76
IS  - 10
SP  - 3861
EP  - 3871
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Shainyan, Bagrat A.
A1  - Kirpichenko, Svetlana V.
A1  - Shlykov, Sergei A.
A1  - Keinpeter, Erich
T1  - Structure and conformational properties of 1,3,3-Trimethyl-1,3-Azasilinane gas electron diffraction, dynamic NMR, and theoretical study
JF  - The journal of physical chemistry : A, Molecules, spectroscopy, kinetics, environment & general theory
N2  - Structure and the conformational properties of 1,3,3-trimethyl-1,3-azasilinane have been studied. According to gas electron diffraction (GED), the molecule exists in a slightly distorted chair conformation with the N-Me group in equatorial position. High-level quantum chemical calculations excellently, reproduce the experimental geometry. Employing variable temperature H-1 and C-13 NMR spectroscopy down to 103 K, the conformational equilibrium could be frozen and the barrier to ring inversion determined.
Y1  - 2012
U6  - https://doi.org/10.1021/jp2110852
SN  - 1089-5639
VL  - 116
IS  - 1
SP  - 784
EP  - 789
PB  - American Chemical Society
CY  - Washington
ER  -