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1.
Summary TheLIS data of 5-(3-N,N-dimethylaminopropyl)-5H-dibenzo[a,d]cycloheptene (1), 5-(3-N,N-dimethyl-and 5-(3-N-methylaminopropylidene)-10,11-dihydro-5H-dibenzo[a,d]-cycloheptene (2,2a) and 5-(3-N,N-dimethylaminopropyl)-10,11-dihydro-5H-dibenzo[a,d]cycloheptene (3) were used to calculate populations of possible conformers in solution. The substrate geometries of the particular conformers were taken from force field calculations. ALIS simulation program was used which is able to handle up to four possible conformations. The limits and special features of the method for highly flexible structures — especially for the case that the coordinating group is within a flexible chain — are discussed.
Konformationsanalyse von 5-H-Dibenzo[a,d]cyclohepten-Derivaten mit flexiblen aminosubstituierten Seitenketten mittels Lanthaniden-induzierter Verschiebungen. Konformationsanalyse hochflexibler Strukturen, 3. Mitt.
Zusammenfassung DieLIS-Werte von 5-(3-N,N-Dimethylaminopropyl)-5H-dibenzo[a,d]-cyclohepten (1), 5-(3-N,N-Dimethyl- bzw. 5-(3-N-Methylaminopropyliden)-10,11-dihydro-5H-dibenzo[a,d]-cyclohepten (2 bzw.2a) und 5-(3-N,N-Dimethylaminopropyl)-10,11-dihydro-5H-dibenzo[a,d]cyclohepten (3) wurden zur Berechnung von Populationen bevorzugter Konformerer herangezogen. Die Geometrien der einzelnen Konformeren wurden aus Force-Field-Rechnungen entnommen. Es wurde einLIS-Programm verwendet, das bei der Simulation bis zu vier Konformationen berücksichtigen kann. Die Grenzen der Anwendbarkeit der Methode — insbesondere die speziellen Probleme die auftreten, wenn die Koordinationsstelle innerhalb einer flexiblen Kette liegt — werden diskutiert.相似文献
2.
Frank J. Villani Peter J. L. Daniels Claire A. Ellis Thomas A. Mann Kai-Chih Wang 《Journal of heterocyclic chemistry》1971,8(1):73-81
The preparation and properties of four isomeric azadibenzoeycloheptenones 3 and their 10,11-dihydro derivatives 2 are described. The ketones 2 were prepared by cyclization of appropriately substituted phenethylpyridine carboxylic acids and dehydrogenated to 3 . Four monochloro derivatives 24 of the 4-azaketone 2d are also described. 相似文献
3.
The proton NMR spectra of the carbanion of 5H-dibenzo[a, d] cycloheptene (DbcH?) and the nitranion of 5H-dibenz[b, f] azepine (Dba?) have been recorded and interpreted. Numerical values for the ring current in each ring have been estimated by a least squares analysis of the observed chemical shifts, after applying corrections for the excess charges and local electric dipoles. The results point to a strong paramagnetic ring current in the seven-membered ring, the one in DbcH? being larger than in Dba?. 相似文献
4.
Frank J. Villani Elizabeth A. Wefer Thomas A. Mann Joseph Mayer Lydia Peer Alfred S. Levy 《Journal of heterocyclic chemistry》1972,9(6):1203-1207
An improved synthesis of the title compound is described. The base catalyzed condensation of 4-methylnicotinonitrile with benzaldehyde resulted in the isolation of trans- 4 -styrylnicotin-amide ( 2a ) in high yield. Hydrolysis to the acid and heating the acid 3a with polyphosphoric acid (ppa) gave the title compound 1a in good yields. Even higher yields of 1a were obtained in the presence of catalytic quantities of selenium. Also described are two other syntheses of the title compound as well as the preparation of a series of compounds related to 2a (Table I). 相似文献
5.
Wojciech Migda Anna Stankiewicz Edward Szneler Lucyna Ulman Barbara Rys 《Magnetic resonance in chemistry : MRC》2010,48(9):712-717
Temperature‐dependent 1H and 13C‐NMR spectra of the title compounds are presented. Coalescence effects are discussed and assigned to dynamic process—the interconversion of bicyclic system. The free energies of activation covered the range 39–52 kJ/mol. The dioxepane ring adopts twist‐chair (TC) conformation. GIAO/DFT calculation of isotropic shieldings for the set of low‐energy conformations showed that only one conformer is present at 298 K in solution that matched well with experimental data. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
6.
Banafsheh Vahdani Alviri Mehrdad Pourayoubi Abdul Ajees Abdul Salam Marek Ne
as Arie van der Lee Akshara Chithran Krishnan Damodaran 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(1):104-116
The crystal structures of diphenyl (cycloheptylamido)phosphate, C19H24NO3P or (C6H5O)2P(O)(NHC7H13), ( I ), and diphenyl (dibenzylamido)phosphate, C26H24NO3P or (C6H5O)2P(O)[N(CH2C6H5)2], ( II ), are reported. The NHC7H13 group in ( I ) provides two significant hydrogen‐donor sites in N—H…O and C—H…O hydrogen bonds, needed for a one‐dimensional hydrogen‐bond pattern along [100] in the crystal, while ( II ), with a (C6H5CH2)2N moiety, lacks these hydrogen bonds, but its three‐dimensional supramolecular structure is mediated by C—H…π interactions. The conformational behaviour of the phenyl rings in ( I ), ( II ) and analogous structures from the Cambridge Structural Database (CSD) were studied in terms of flexibility, volume of the other group attached to phosphorus and packing forces. From this study, synclinal (±sc), anticlinal (±ac) and antiperiplanar (±ap) conformations were found to occur. In the structure of ( II ), there is an intramolecular Cortho—H…O interaction that imposes a +sc conformation for the phenyl ring involved. For the structures from the CSD, the +sc and ±ap conformations appear to be mainly imposed by similar Cortho—H…O intramolecular interactions. The large contribution of the C…H/H…C contacts (32.3%) in the two‐dimensional fingerprint plots of ( II ) is a result of the C—H…π interactions. The differential scanning calorimetry (DSC) analyses exhibit peak temperatures (Tm) at 109 and 81 °C for ( I ) and ( II ), respectively, which agree with the strengths of the intermolecular contacts and the melting points. 相似文献
7.
A. I. Uraev A. L. Nivorozhkin G. I. Bondarenko K. A. Lysenko O. Yu. Korshunov V. G. Vlasenko A. T. Shuvaev V. P. Kurbatov M. Yu. Antipin A. D. Garnovskii 《Russian Chemical Bulletin》2000,49(11):1863-1868
Copper(II) chelates of composition CuL2 were synthesized based on 4-aminomethylene derivatives of 5-thiopyrazoles (LH). The complexes were studied by UV, IR, ESR,
and EXAFS spectroscopy, magnetochemistry, and X-ray diffraction analysis. The coordination polyhedra in the complexes are
pseudotetrahedra or octahedra of the types CuN2S2 or CuN4S2, respectively, which are distorted due to the Jahn—Teller effect. The UV and ESR spectra of copper chelates with a six-coordinate
metallocycle formed by the N and S atoms of the azomethine ligand and the nitrogen atom of the quinoline substituent (R) of
the C=N−R fragment are most similar to the spectra observed for metals involved in the active centers of natural metalloenzymes
(“blue” copper proteins).
Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1891–1896, November, 2000. 相似文献