Vibrational spectra, X-ray and molecular structure of 1H- and 3H-imidazo[4,5-b]pyridine and their methyl derivatives: DFT quantum chemical calculations

2008 ◽  
Vol 39 (1) ◽  
pp. 1-15 ◽  
Author(s):  
J. Lorenc ◽  
L. Dymińska ◽  
Z. Talik ◽  
J. Hanuza ◽  
M. Mączka ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Quantum Chemical Calculations ◽  
Vibrational Spectra ◽  
Quantum Chemical ◽  
X Ray ◽  
Methyl Derivatives

scholarly journals Synthesis of Bis(Carboranyl)amides 1,1′-μ-(CH2NH(O)C(CH2)n-1,2-C2B10H11)2 (n = 0, 1) and Attempt of Synthesis of Gadolinium Bis(Dicarbollide)

Molecules ◽  
2021 ◽  
Vol 26 (5) ◽  
pp. 1321
Author(s):  
Yasunobu Asawa ◽  
Aleksandra V. Arsent’eva ◽  
Sergey A. Anufriev ◽  
Alexei A. Anisimov ◽  
Kyrill Yu. Suponitsky ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Single Crystal ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
X Ray Diffraction ◽  
Stable Conformation ◽  
Acyl Chlorides ◽  
X Ray ◽  
Cesium Fluoride ◽  
The Stability

Bis(carboranyl)amides 1,1′-μ-(CH2NH(O)C(CH2)n-1,2-C2B10H11)2 (n = 0, 1) were prepared by the reactions of the corresponding carboranyl acyl chlorides with ethylenediamine. Crystal molecular structure of 1,1′-μ-(CH2NH(O)C-1,2-C2B10H11)2 was determined by single crystal X-ray diffraction. Treatment of bis(carboranyl)amides 1,1′-μ-(CH2NH(O)C(CH2)n-1,2-C2B10H11)2 with ammonium or cesium fluoride results in partial deboronation of the ortho-carborane cages to the nido-carborane ones with formation of [7,7′(8′)-μ-(CH2NH(O)C(CH2)n-7,8-C2B9H11)2]2−. The attempted reaction of [7,7′(8′)-μ-(CH2NH(O)CCH2-7,8-C2B9H11)2]2− with GdCl3 in 1,2-dimethoxy- ethane did not give the expected metallacarborane. The stability of different conformations of Gd-containing metallacarboranes has been estimated by quantum-chemical calculations using [3,3-μ-DME-3,3′-Gd(1,2-C2B9H11)2]− as a model. It was found that in the most stable conformation the CH groups of the dicarbollide ligands are in anti,anti-orientation with respect to the DME ligand, while any rotation of the dicarbollide ligand reduces the stability of the system. This makes it possible to rationalize the design of carborane ligands for the synthesis of gadolinium metallacarboranes on their base.

scholarly journals 6,6′-Dimethyl-1,1′,5,5′-tetraaza-6,6′-bi(bicyclo[3.1.0]hexane): synthesis and investigation of molecular structure by quantum-chemical calculations, NMR spectroscopy and X-ray diffraction analysis

2021 ◽  
Author(s):  
Inna Nikolaevna Kolesnikova ◽  
Vladimir Vladimirovich Kuznetsov ◽  
Alexander Sergeevich Goloveshkin ◽  
Nikolai Andreevich Chegodaev ◽  
Nina Nikolaevna Makhova ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Nmr Spectroscopy ◽  
Diffraction Analysis ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
X Ray Diffraction ◽  
X Ray

Sterically Crowded Heterocycles. VIII. Preparative Photoisomerization of Some Imidazo[1,2-a]pyridines

1996 ◽  
Vol 61 (10) ◽  
pp. 1473-1488 ◽  
Author(s):  
Richard Kubík ◽  
Stanislav Böhm ◽  
Jan Čejka ◽  
Vladimír Havlíček ◽  
Tomáš Strnad ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Mass Spectra ◽  
X Ray ◽  
Uv Illumination ◽  
Derivatives Of ◽  
Semiempirical Quantum Chemical Calculations

UV-Illumination of (Z)-3-(2-phenylimidazo[1,2-a]pyridin-3-yl)-1,3-diphenylprop-2-en-1-one (1a) or its 6-methyl and 6-iodo derivatives 1c and 1g resulted in minor (E)-isomers 2a, 2c, and 2g and prevailing (E,Z)-mixtures of N-(pyridin-2-yl)-[(3,5-diphenylfuran-2-yl)phenylmethylidene]amines 3a, 3c, and 3g while only corresponding furanoic derivatives 3b and 3d-3f were obtained from 5-methyl (1b), 7-methyl (1d), 8-methyl (1e), and 5-phenyl (1f) derivatives of the (Z)-ketone 1a. VIS-Illumination of (Z)-1,3-diphenyl-3-(2-phenylimidazo[1,2-a]benzo[I]quinolin-3-yl)prop-2-en-1-one (4) led to N-(benzo[h]quinolin-2-yl)-[(3,5-diphenylfuran-2-yl)phenylmethylidene]amine (5). Photoisomers 2a, 2c, 2g, 3a-3g, and 5 were isolated and the molecular structure of 3c was X-ray determined. Mechanism of the photoisomerization is discussed using semiempirical quantum chemical calculations and compared with mass spectra of compounds 1a, 2a, 3a, 1g, 2g, and 3g.

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