Isolation and oxidation-reduction of methylviologen cation radicals. Novel disproportionation in charge-transfer salts by x-ray crystallography

1990 ◽  
Vol 55 (13) ◽  
pp. 4127-4135 ◽  
Author(s):  
T. M. Bockman ◽  
J. K. Kochi
2017 ◽  
Vol 53 (18) ◽  
pp. 2748-2751 ◽  
Author(s):  
Maxim V. Ivanov ◽  
Khushabu Thakur ◽  
Anshul Bhatnagar ◽  
Rajendra Rathore

Chiral cation-radicals hold significant promise as charge-transfer materials, chiroptical switches, and catalysts for enantioselective synthesis. Herein we identify a chiral anthracene derivative that forms a robust cation-radical salt as established by X-ray crystallography and DFT calculations.


Author(s):  
S. L. Hill ◽  
K. Krishnan ◽  
J. R. Ferraro

Certain classes of organic charge-transfer salts demonstrate superconducting behavior at liquid helium temperatures. Single crystal x-ray diffraction and infrared microreflectance analysis have been performed on several conducting systems to associate the nature of the crystalline structure with the electrical conductivity. The infrared spectrum for a single crystal salt exhibits absorptions which correlate with superconducting behavior.Discussion Williams and coworkers have performed x-ray Crystallography experiments to demonstrate the presence of an anion cavity between radical cation stacks- of bis(ethylenedithio)- tetrathiafulvalene (ET). The sulfur…sulfur interstack distance in a beta or kappa phase salt assumes a value less than the Vanderwaals distance and exhibit a superconducting (two dimensional) metal behavior (verified by Fermi surface calculations) at 1-20K. The structures of alpha and beta phase ET2I3 suggest the potential for several potential intermolecular interaction modes. It may be observed that the beta phase permits both interstack as well as H … X anionic interactions, whereas these interactions are less likely to occur in the alpha phase.


Author(s):  
Jean-Paul Pouget

AbstractQuasi-one dimensional (1D) conductors of the TTF-TCNQ family of charge transfer salts exhibit a Peierls transition which stabilizes a periodic lattice distortion (PLD), accompanied by a charge density wave (CDW) modulation, with an incommensurate 2


1996 ◽  
Vol 506 (1-2) ◽  
pp. 203-210 ◽  
Author(s):  
Elena Cerrada ◽  
M. Concepción Gimeno ◽  
Antonio Laguna ◽  
Mariano Laguna ◽  
Victor Orera ◽  
...  

1999 ◽  
Vol 77 (5-6) ◽  
pp. 913-921 ◽  
Author(s):  
Rajendra Rathore ◽  
Jay K Kochi

The conformational preference of vicinal or 1,2-phenyl groups is probed in two classes of ring-substituted 1,2-diphenylbicyclooctene (stilbenoid) hydrocarbons 1a-1d and 2a-2c. UV-vis spectroscopy reveals, and X-ray crystallography verifies, the intramolecular (edge-to-face) orientation for the phenyl-phenyl interaction in stilbenoids 1a-1d. Most importantly, when two pairs of ortho-methyl substituents are present, the cofacial phenyl groups in the stilbenoid donors are established by X-ray crystallography and spectrally observed in the cation radicals (2a+.-2c+.) by the appearance of new bands with strong absorptions in the near IR with λmax = 1100-1315 nm, analogous to those previously observed in intermolecular (aromatic) interactions of aromatic cation radicals.Key words: stilbenoid hydrocarbon, cation radical, aryl-aryl interaction.


Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 467
Author(s):  
Qi Feng ◽  
Wenhui Huan ◽  
Jiali Wang ◽  
Jiadan Lu ◽  
Guowang Diao ◽  
...  

Two novel 1,3,5-trisubstituted pyrazoline derivatives—1-acetyl-3-(4-methoxyphenyl)-5-(6-methoxy-2-naphthyl)-pyrazoline (2a) and 1-(4-nitrophenyl)-3-(4-methoxyphenyl)-5-(6-methoxy-2-naphtyl)-pyrazoline (2b)—were synthesized and their structures were determined by single crystal X-ray crystallography. Both of the two crystals exhibit twisted structures due to the large dihedral angles between the pyrazolinyl ring and the aromatic ring at the 5-position (88.09° for 2a and 71.26° for 2b). The optical–physical properties of the two compounds were investigated. The fluorescent emission of 2b arises from the 1,3-disubstituted pyrazoline chromophores and exhibits a red shift in polar solvents and solid-state, which could be attributed to photo-induced intramolecular charge transfer (ICT) from N1 to C3 in the pyrazoline moiety and the intermolecular interactions within the crystal. The fluorescent emissions of 2a (λmax 358–364 nm) in solvents and solid-state both come from 6-methoxy-2-naphthyl chromophores, which are fairly insensitive to the solvent polarity.


1999 ◽  
Vol 102 (1-3) ◽  
pp. 1707-1708 ◽  
Author(s):  
A. Pérez-Benítez ◽  
C. Rovira ◽  
J. Veciana ◽  
J. Vidal-Gancedo ◽  
V.N. Laukhin ◽  
...  

2006 ◽  
Vol 20 (25n27) ◽  
pp. 4619-4624 ◽  
Author(s):  
NAZRUL ISLAM ◽  
MASAO TSUKAYAMA ◽  
YASUHIKO KAWAMURA

The charge-transfer reaction of tetraarylbutatriene 1 with tetracyanoethene (TCNE) in dichloromethane at room temperature was studied and we found a novel addition reaction. A red crystalline material 2 was isolated as an intermediate product which is converted slowly into dihydronaphthalene derivative 3 in dichloromethane but rapidly in protic solvent. The structure of the compounds was determined by X-ray crystallography. The detailed structure and the plausible reaction mechanism have also been discussed.


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