The Experts below are selected from a list of 399 Experts worldwide ranked by ideXlab platform
Werner Schroth - One of the best experts on this subject based on the ideXlab platform.
-
Molecular structures and electronic transitions of 3,6-diphenyl-1,2-Dithiin and its radical cation: a spectroelectrochemical and DFT study.
The journal of physical chemistry. A, 2006Co-Authors: Horst Hennig, Werner Schroth, Roland Spitzner, Frank Schumer, Joachim Reinhold, Heiner Kaden, Wolfram Oelssner, František HartlAbstract:One-electron oxidation of 3,6-diphenyl-1,2-Dithiin yields the corresponding radical cation. The product is stable at low temperatures and can be distinguished by a triplet EPR signal. Cyclic voltammetric, UV-vis spectroelectrochemical, and DFT studies were performed to elucidate its molecular structure and electronic properties. Time-dependent DFT calculations reproduce appreciably well the UV-vis spectral changes observed during the oxidation. The results reveal a moderately twisted structure of the 1,2-Dithiin heterocycle in the radical cation.
-
oxidation of z z 1 4 diaminobuta 1 3 diene 1 4 dithiolates and related precursors alternatives for 1 2 Dithiin formation
European Journal of Organic Chemistry, 2000Co-Authors: Werner Schroth, Roland Spitzner, Michael Felicetti, Christoph Wagner, Clemens BruhnAbstract:Oxidation of the title compounds, in contrast to that of “normal” (Z,Z)-buta-1,3-diene-1,4-dithiolates, does not lead to the formation of 1,2-Dithiins. Thus, the aliphatic diaminodithiolates 7 and 8 were converted into the (E)-2-butenedithioamides 12 and 15 as a result of resonance stabilization of the thiocarbonyl group. On the other hand, the 3,3′-biindole-2,2′-dithiolate 9, the aromatic counterpart of 8, undergoes disulfide formation with preservation of aromaticity in the hetarene rings and yields the 1,2-Dithiin dimer 31 with a 12-membered ring structure. In this instance, the formation of the expected (E)-3,3′-biindolinylidene-2,2′-dithione 29 (a thioxo analogue of isoindigo) does not take place, paralleling the general problems for the existence of thioxo indigoid compounds 37. On the other hand, oxidation of the 2,2′-bi-hetarene-3,3′-dithiolates 34 [formally, (Z,Z)-buta-1,3-diene-1,4-dithiolates with π-donor substituents X in the 2- and 3-positions] affords either monomeric (38c) or dimeric 1,2-Dithiins (e.g. 39a,b,d) depending on the heteroatom X in the anellated hetarene ring. It was possible to correct some longstanding erroneous structures: such as the 3,6-diamino-1,2-Dithiins 20 in favor of the (E)-2-butenedithioamides 22, and the alleged thioxoisoindigo 29 − obtained from 1-methylindoline-2-thione (23) and N,N-dimethyl-4-nitrosoaniline − in favor of the 1,2-Dithiin dimer 31.
-
bis benzo 4 5 thieno 3 2 c 2 3 e 1 2 Dithiin ein valenzisomer von dithioxo thioindigo
Chemische Berichte, 1994Co-Authors: Werner Schroth, E Hintzsche, Horst Viola, Ralf Winkler, Heike Klose, Roland Boese, Rhett Kempe, Joachim SielerAbstract:Bis(benzo[4,5]thieno)[3,2-c:2′,3′-e][1,2]Dithiin, ein Valenzisomer von „Dithioxo-thioindigo” 3-Mercaptobenzo[b]thiophene (1) is transformed with assistance of bases, especially of amines, into the benzo[b]-thieno-annellated 1,2-Dithiine 6 and not into the originally claimed “Dithioxo-thioindigo” trans-3. Primarily, the formation of 6 from 1 involves oxidation to the disulfide 4 which may also be used separately. Conceivable rationalizations are discussed. The same compound is accessible (in lower yield)by thionation of thioindigo with the aid of the Lawesson reagent. X-ray elucidation of 6 reveals a non-planar structure of the cyclic disulfide with a dihedral CSSC-angle of 53°. Despite of the absence of any established chromonphoric moiety, 6 is deeply red in the crystal and in solution, as it is representative for the “undisturbed” 1,2-Dithiine system. Contrary to the usual behaviour of the non-annellated 1,2-Dithiines, 6 displays no spontaneous sulfur extrusion under mild conditions, but only at high temperatures and in the presence of sulfur-binding agents, leading to the benzo[b]thieno-annellated thiophene 22. Moreover, 6 may be reduced to the dithiol 14 (or 13, respectively) and regenerated exclusively from this by oxidation. Further characteristic reactions of 6 are described (e.g. to the sulfoxide 18, to the pyridazine 19, and to the thiphosphoric ester 21).
Liran Jia - One of the best experts on this subject based on the ideXlab platform.
-
zinc ιι complexes with 5 6 dihydro 1 4 Dithiin 2 3 dicarboxylic anhydrate and different n donors syntheses crystal structures and emission properties
Journal of Coordination Chemistry, 2012Co-Authors: Shaoming Fang, Donglai Peng, Min Chen, Liran JiaAbstract:Two new ZnII complexes, {[Zn(L)(phen)(H2O)] · H2O}∞ (1) and {[Zn(L)(4bpy)(H2O)] · H2O}∞ (2) (L = 5,6-dihydro-1,4-Dithiin-2,3-dicarboxylate, phen = 1,10-phenanthroline, and 4bpy = 4,4′-bipyridine), have been prepared by in situ reaction of Zn(ClO4)2 · 6H2O with 5,6-dihydro-1,4-Dithiin-2,3-dicarboxylic anhydrate in the presence of lithium hydroxide, together with incorporating chelating phen or bridging 4bpy as co-ligands. Their structures were determined by single-crystal X-ray diffraction. Complex 1 takes a 1-D helical structure that is further assembled into a 2-D network by O–H ··· O, C–H ··· O hydrogen bonds, and weak S ··· S interactions, and then an overall 3-D supramolecular framework was formed by π ··· π stacking interactions. Complex 2 possesses a 2-D (4,4)-layered structure. The structural difference between 1 and 2 can be attributed to the different N-donor auxiliary co-ligands. Both 1 and 2 are photoluminescent materials whose emission properties are closely related to their intrinsic structure.
Dong-youn Noh - One of the best experts on this subject based on the ideXlab platform.
-
electrochemistry and strong near ir absorption of the ni dphdt 2 n complexes n 1 0 dphdt 5 6 diphenyl 1 4 Dithiin 2 3 dithiolate x ray crystal structure of ph4p ni dphdt 2 ch2cl2
Polyhedron, 2000Co-Authors: Ha-jin Lee, Dong-youn NohAbstract:Abstract Nickel bisdithiolene complexes Cx[Ni(dphdt)2] (x=1 or 0.1, C=tetrabutylammonium (n-Bu4N+); x=1, C=tetraphenylphosphonium (Ph4P+); dphdt=5,6-diphenyl-1,4-Dithiin-2,3-dithiolate) have been synthesized and characterized. The molecular structure of (Ph4P)[Ni(dphdt)2](CH2Cl2) was determined by X-ray analysis. Ni(S2C2S2)2 core is planar and stacking along the c-axis and the shortest intra-stack S⋯S distance is 4.529 A. According to the cyclic voltammetry of (n-Bu4N)[Ni(dphdt)2], two phenyl groups on the dphdt ligand decrease the electron density on the Ni(S2C2S2)2 core and increase the oxidation potentials compared to those of the (n-Bu4N)[Ni(dddt)2] complex (dddt=5,6-dihydro-1,4-Dithiin-2,3-dithiolate). Near-IR spectra of the complexes show that phenyl substitution on the ligand does not give rise to the evident change in transition energy due to the lack of coplanarity with the Ni(S2C2S2)2 core.
-
Synthesis and Characterization of Two Different 1,3-Dithiole-2-thiones as the Precursors of TTF Donor Molecule
2000Co-Authors: Young-youn Kim, Ha-jin Lee, Sung Keon Namgoong, Jongki Hong, Dong-youn NohAbstract:W X# YZ#%&. ABSTRACT. As a precursor of tetrathiafulvalene (TTF) derivative, 5,6-dimethyl-1,3-dithiolo[4,5-b][1,4] Dithiin-2-thione (compound 3) was synthesized by the unusual Lawesson’s reaction. Depending upon the sub-stituents such as dimethyl and diphenyl groups, two different products containing 1,4-Dithiin and thiophene moieties, respectively, were obtained and characterized by 13C NMR and high-resolution electron impact (HREI) mass spectroscopy. The formation of 3 was further characterized by X-ray structure analysis. Crys-tallographic data for 3: triclinic, space group P1, a=4.145(2)Å, b=10.600(2)Å, c=12.279(2)Å, α=71.440(10)o, β=84.30(2)o, γ=87.31(2)o, Z=2 and R(wR2)=0.0559(0.1416). The formation mechanism of two products was suggested and compared each other
-
syntheses x ray crystal structures andproperties of di and tetra ferrocenyl nickel bis 1 4 Dithiin 5 6 dithiolate complexes
Journal of Materials Chemistry, 2000Co-Authors: Ha-jin Lee, Dong-youn NohAbstract:Tetra-n-butylammonium salts of nickel-bis(2-ferrocenyl-1,4-Dithiin-5,6-dithiolate) (1; TBA[Ni(fcvdt)2]) and nickel-bis(2,3-diferrocenyl-1,4-Dithiin-5,6-dithiolate) (2; TBA[Ni(dfcvdt)2]) have been successfully synthesized. The crystal structures of complex 1 and 2 were determined by X-ray analysis. The [Ni(fcvdt)2]− anion has a chair-like conformation with the two ferrocenyl groups folding up and down while the [Ni(dfcvdt)2]− anion has a boat-like conformation with four ferrocenyl groups folding up. Cyclic voltammograms of these complexes show two reversible redox peaks at around −0.9 V and −0.2 V (Ag/Ag+, THF) associated with the Ni(II) dithiolate complex and one quasi-reversible peak associated with the ferrocenyl moieties. The complexes exhibit a strong near-IR absorption at 1178 nm (log e = 3.99) for complex 1 and at 1155 nm (log e = 4.06) for complex 2. This suggests the possibility of utilizing these complexes as near-IR dyes for absorbing lower energy.
F Iwasaki - One of the best experts on this subject based on the ideXlab platform.
-
syntheses and structures of novel fused ring systems containing six or seven sulfur atoms 2 3 5 6 bis ethylenedithio thieno 3 2 b thiophene and 3 4 6 7 bis ethylenedithio thieno 3 2 c 1 2 Dithiin
Bulletin of the Chemical Society of Japan, 1995Co-Authors: Motoko Tanaka, Toshimasa Ishida, Takashi Nogami, Hajime Yoshikawa, M Yasui, F IwasakiAbstract:Novel fused-ring molecules, 2,3:5,6-bis(ethylenedithio)thieno[3,2-b]thiophene and 3,4:6,7-bis(ethylenedithio)thieno[3,2-c][1,2]Dithiin, were synthesized for the development of new conducting organic salts. They have six and seven sulfur atoms, respectively. Their molecular and crystal structures were determined by X-ray crystallographic analyses. Their oxidation potentials were measured, compared with those of the related donor molecules, and analyzed by a molecular-orbital calculation.
Tadashi Sugawara - One of the best experts on this subject based on the ideXlab platform.
-
New synthesis of 2-[1,3-dithiol-2-ylidene]-5,6-dihydro-1,3-dithiolo[4,5-b][1,4]Dithiins with formyl group on fused benzene, [1,4]Dithiin, or thiophene ring
Tetrahedron Letters, 1999Co-Authors: Yoshihiro Ishikawa, Tomoko Miyamoto, Asami Yoshida, Yuzo Kawada, Jotaro Nakazaki, Akira Izuoka, Tadashi SugawaraAbstract:Abstract As novel TTF-based annelated donors, 2-[1,3-dithiol-2-ylidene]-5,6-dihydro-1,3-dithiolo[4,5- b ][1,4]Dithiins with a formyl group on fused benzene, [1,4]-Dithiin, or thiophene ring, respectively, were prepared using Diels-Alder or an intramolecular aldol reaction.
