TY  - JOUR
A1  - Kleinpeter, Erich
A1  - Thomas, Steffen
A1  - Uhlig, G.
A1  - Rudorf, Wolf-Dieter
T1  - Study of the distribution of pi-Electrons in Push-Pull Alkenes by 1H an 13C NMR spectroscopy
Y1  - 1993
ER  - 
TY  - JOUR
A1  - Kleinpeter, Erich
A1  - Thomas, Steffen
A1  - Fischer, G.
T1  - 13C and 15N NMR study of 1,2,4-Triazolo[1,5-a]pyrimidines with one tautomerism-introducing substituent
Y1  - 1995
ER  - 
TY  - JOUR
A1  - Thomas, Steffen
A1  - Brühl, Iris
A1  - Heilmann, Dieter
A1  - Kleinpeter, Erich
T1  - 13 C NMR Chemical shift calculations for some substituted pyridines - a comparative consideration
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Koch, Andreas
A1  - Thomas, Steffen
A1  - Kleinpeter, Erich
T1  - Ab-initio study, semi-empirical calculation and NMR spectroscopy of keto-enol tautomerism of triazolopyrimidines
Y1  - 1997
ER  - 
TY  - JOUR
A1  - Benassi, Rois
A1  - Bertarini, C.
A1  - Kleinpeter, Erich
A1  - Taddei, F.
A1  - Thomas, Steffen
T1  - Exocyclic push-pull conjugated compounds : Part 1 ; theoretical study of the effect of ring size on the structure, electronic properties and rotational barriers of cyclic analogoues of 1,1-diamino-2.2-dicyanoethylene
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Benassi, Rois
A1  - Bertarini, C.
A1  - Hilfert, Liane
A1  - Kempter, Gerhard
A1  - Kleinpeter, Erich
A1  - Spindler, Jürgen
A1  - Taddei, F.
A1  - Thomas, Steffen
T1  - Exocyclic push-pull conjugated compounds : Part 3
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Miklos, F.
A1  - Kanizsai, I.
A1  - Thomas, Steffen
A1  - Kleinpeter, Erich
A1  - Sillanpaa, R.
A1  - Stajer, G.
T1  - Preparation and structure of diexo-oxanorbornane-fused 1,3-heterocycles
N2  - Via the reaction of diexo-oxanorbornanedicarboxylic anhydride with toluene, the diexo-aroylcarboxylic acid (3a) was prepared, which exists partly as the tautomeric lactol (3b). With bifunctional reagents, 3a yields fused heterocycles containing three-six rings. Thus, alkylenediamines result in imidazole- and 1,3-diazepine-fused oxygen- bridged isoindolones (6a,b), alkanolamines form the oxazole- and 1,3-oxazine-fused oxanorbornene derivatives (7a-c), and o-phenylenediamine undergoes cyclization to furnish the condensed benzimidazole (8). The reaction of 3a with diexo- aminonorbornanecarbohydrazide yields a pyrimidopyridazine containing six condensed rings (9). In a similar reaction with diendo-aminonorbornenecarbohydrazide, cyclopentadiene cleaves off to give the tricyclic retro Diels-Alder product (10). The structures, and particulary the configurations at the oxanorbornane ring systems and the position of the aryl substituent, were established by means of 1D- and 2D-NMR spectroscopy and, for 3b and 7c, also by X-Ray measurements
Y1  - 2004
SN  - 0385-5414
ER  - 
TY  - JOUR
A1  - Thomas, Steffen
A1  - Kleinpeter, Erich
T1  - A novel empirical approach for the structure elucidation of disilanes by empirical estimation of their Si-29 chemical shifts
N2  - In C-13 NMR spectroscopy, there are many empirical methods for fast and exact computation of C-13 chemical shifts; comparable procedures for Si-29 NMR chemical shifts are not existing or are older than 20 years. On basis of the largest database of Si-29 chemical shifts available, along this paper a relatively simple procedure for the similarly exact calculation of the Si-29 chemical shifts of disilanes (average margin of error ca. 3.7 ppm) is given. (c) 2005 Elsevier B.V. All rights reserved
Y1  - 2005
SN  - 0022-2860
ER  -