34507
2013
2013
eng
10849
10857
9
51
69
article
Elsevier
Oxford
1
--
--
--
Studies of the regioselective ring-opening closing mode of functionally different thiazolidine type enaminones - en route to the synthesis of trithiaazapentalene derivatives
Trithiaazapentalene derivatives were prepared by the reaction of 2-alkylidene-4-oxothiazolidines with Lawesson's reagent. They are classified as two structurally different trithiaazapentalene compounds that have different contributions of monocyclic 1,2-dithiole and 1,2,4-dithiazole structures and degrees of aromaticity of the bicyclic trithiaazapentalene system. The electron-donating ability of substituents at the C(5) position of the trithiaazapentalene system is recognized as the main cause for changes in pi-Celectron distribution. This is the first complete study of substituent effects on the structure of trithiapentalenes. (C) 2013 Elsevier Ltd. All rights reserved.
Tetrahedron
10.1016/j.tet.2013.10.088
0040-4020
wos:2011-2013
WOS:000328808300009
Rasovic, A (reprint author), Univ Belgrade, Ctr Chem ICTM, POB 473, Belgrade 11000, Serbia., arasovic@chem.bg.ac.rs
Ministry of Education, Science and Technological Development of the
Republic of Serbia [172020]; Deutscher Akademischer Austauschdienst
(DAAD)-project [504 252 70]
Aleksandar Rasovic
Andreas Koch
Erich Kleinpeter
Rade Markovic
eng
uncontrolled
Trithiapentalene
eng
uncontrolled
1,2-Dithiole
eng
uncontrolled
1,2,4-Dithiazole
eng
uncontrolled
4-Oxothiazolidine
eng
uncontrolled
Rearrangement to trithiaazapentalene
eng
uncontrolled
Push-pull character
Institut für Chemie
Referiert
35141
2013
2013
eng
2436
2445
10
11
69
article
Elsevier
Oxford
1
--
--
--
Push-pull allenes-conjugation, (anti)aromaticity and quantification of the push-pull character
Structures, H-1/C-13 chemical shifts, and pi electron distribution/conjugation of an experimentally available and theoretically completed set of push-pull allenes Acc(2)C=C=CDon(2) (Acc=F, CHO, CF3, C N; Don=t-Bu, OMe, OEt, SMe, SEt, NCH2R) have been computed at the OFT level of theory. Both orthogonal linear and orthogonal bent structures have been obtained. In the latter case the push-pull character could be quantified by the quotient method. The C-13 chemical shift of the central allene carbon atom C-2 and chemical shift differences Delta delta(C-1, C-2) and Delta delta(C-2, C-3) of allene carbon atoms proved to be a quantitative alternative. TSNMRS of ring-closed push-pull allenes have been computed in addition and were employed to identify polar, carbene-like and carbone-like canonical structures of these molecules.
Tetrahedron
10.1016/j.tet.2013.01.027
0040-4020
wos:2011-2013
WOS:000315372500004
Kleinpeter, E (reprint author), Univ Potsdam, Inst Chem, Karl Liebknecht Str 24-25, D-14476 Golm, Germany., ekleinp@uni-potsdam.de
Erich Kleinpeter
Peter Werner
Andreas Koch
eng
uncontrolled
Push-pull allenes
eng
uncontrolled
Push-pull character
eng
uncontrolled
C-13 NMR spectroscopy
eng
uncontrolled
Quotient method
eng
uncontrolled
TSNMRS
eng
uncontrolled
ICSS
eng
uncontrolled
Aromaticity
Institut für Chemie
Referiert