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Anjan K. Saha M. Mahmun Hossain Desiree S. Grubisha Dennis W. Bennett 《Journal of chemical crystallography》1995,25(7):383-387
Benzophenone azine crystallizes in the monoclinic space groupA2/a (No. 15) witha=16.303(3) Å,b=5.4864(2) Å,c=21.973(5) Å, =85.52(2)°,V=1959.4(8) Å3, andD
calc=1.22 g cm–3 forZ=4. The structure was solved by direct methods and refined againstF to a finalR value of 0.047. The unit cell contains four molecules of the title compound; the asymmetric unit consists of half a molecule. Despite the high crystallographic symmetry, the two halves of the molecule arenot related by a center of symmetry; instead, the molecule adopts C2 symmetry; the molecular C2 axis is coincident with the crystallographic twofold axis. The formation of benzophenone azine from the reaction of the iron-containing Lewis acid complex [(5-C5H5)Fe(CO)2(THF)]+ [BF4]– and diphenyldiazomethane provides strong evidence for an Fe(II) carbene intermediate. 相似文献
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吲唑类化合物合成新方法的研究(Ⅰ) 总被引:1,自引:0,他引:1
本文研究了2,6-二烷氧基苯乙酮腙在多聚磷酸(PPA)存在下受热脱去一分子醇环化生成3-甲基-4-烷氧基吲唑的合成反应.并研究了水杨醛、邻甲氧基苯甲醛、2,4-二羟基苯甲醛以及邻羟基苯乙酮、2-羟基-3,5-二甲基苯乙酮腙在PPA存在下的受热反应过程. 相似文献
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Maurizio D’Auria 《Tetrahedron letters》2005,46(37):6333-6336
The low reactivity of pyridine, pyridazine, pyrazine, pyrimidine, and purine toward electrophilic substitution reactions can be explained assuming a frontier orbitals control of the reaction. DFT study of the molecular orbitals of these molecules shows that the HOMOs of these substrates are not π orbitals. Furthermore, the change in the reactivity observed in pyridine-N-oxide, in activated pyrimidines, and in activated purines can be explained considering that, in this case, the HOMOs are π orbitals. 相似文献
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H. A. Derbala 《Monatshefte für Chemie / Chemical Monthly》1996,127(1):103-110
Summary 6-Bromo-2-methyl-3,1-benzoxazin-4-one (1) undergoes an unusual cleavage at position 4 when it is allowed to react witho-phenylenediamine or anthranilic acid in dry benzene to give the corresponding compounds2–5, respectively. The reaction of1 withSchiffbases and azines results in the formation of the compounds6a–d and8a,b, respectively. The reaction involves a cleavage of theSchiff base or the azine into its amine and arylidene moieties which are smoothly incorporated into1
via nucleophilic attack of the amine at position 4 and condensation of the aldehyde with a reactive methyl group, at position 2 respectively. No displacement of the arylidene segment was observed.
Zur Chemoselektivität von 6-Brom-2-methyl-3,1-benzoxazin-4-on gegenüber Aminen,Schiffschen Basen und Azinen
Zusammenfassung 6-Brom-2-methyl-3,1-benzoxazin-4-on reagiert mito-Phenylendiamin oder Anthranilsäure in trockenem Benzol unter einer ungewöhnlichen Bindungstrennung zu den Verbindungen2–5. Die Reaktion von1 mitSchiffschen Basen und Azinen führt zu den Verbindungen6a–d und8a,b. Die Reaktion verläuft über eine Spaltung derSchiffschen Base oder des Azins in ihre Amin- und Arylidenreste, die über einen nucleophilen Angriff des Amins an Position 4 und Kondensation des Aldehyds mit der reaktiven Methylgruppe in Position 2 glatt in1 übergeführt werden. Es wurde kein Arylidenaustausch beobachtet.相似文献
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Vjacheslav Lapachev Svetlana Stekhova Vladimir Mamaev 《Monatshefte für Chemie / Chemical Monthly》1987,118(5):669-670
The tautomeric properties ofo-hydroxyphenylazines have been investigated by17O NMR and UV spectroscopy. 2-(o-Hydroxyphenyl)-pyridine and itsp-nitrophenole analog II exist in chloroform or ethanol as a phenol A. In the case of 2-(2-hydroxy-5-nitrophenyl)-quinoline the NH-tautomer is realized, the content of which increases when going to the dinitro-analog IV.
Die Tautomerie von 2-(o-Hydroxyphenyl)-azinen (Kurze Mitteilung)
Zusammenfassung Es wurden die tautomeren Eigenschaften vono-Hydroxyphenylazinen mittels17O-NMR und UV-Spektroskopie untersucht. 2-(o-Hydroxyphenyl)-pyridin und seinp-Nitrophenol-Analog II existieren in Chloroform und Ethanol als Phenol A. Das 2-(2-Hydroxy-5-nitrophenyl)-chinolin liegt als NH-Tautomer vor, dessen Anteil im Dinitro-Analog IV noch steigt.相似文献
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Norbert Müller Vjacheslav V. Lapachev 《Monatshefte für Chemie / Chemical Monthly》1987,118(10):1201-1204
15N-1H coupling constants can be measured over a large range by means of the Broadband-INEPT NMR-technique. These coupling constants are used to determine the positions of tautomeric equilibria of 2-(acetylmethyl)-azines with high accuracy.
Die Anwendung von1H—15N-Kopplungskonstanten bei Untersuchungen von Tautomerengleichgewichten von Azinen (Kurze Mitteilung)
Zusammenfassung Mittels der Breitband-INEPT NMR-Technik können15N-1H-Kopplungskonstanten über einem weiten Bereich gemessen werden. Aus diesen Kopplungskonstanten kann die Lage der Tautomerengleichgewichte von 2-(Acylmethyl)-azinen mit großer Genauigkeit bestimmt werden.相似文献
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A series of mononuclear indenyl and pentamethylcyclopentadienyl ruthenium(II) complexes of formulation [(η5-L3)Ru(PPh3)(L2)]X, (where L3 = indenyl, pentamethylcyclopentadienyl; X = PF6 or BF4 and L2 = azine ligands) have been prepared by the reaction of [(η5-L3)Ru(PPh3)2(CH3CN)]X with the appropriate azine ligands in methanol or dichloromethane/benzene mixture. The reaction of nitro substituted azine ligands with the complexes [(η5-L3)Ru(PPh3)2(CH3CN)]X are solvent dependent. All these complexes were isolated as their PF6 or BF4 salts. The complexes were fully characterized with the help of microanalyses, FT-IR and NMR spectroscopy. The molecular structure of representative complexes 5c and 6a were established by single X-ray crystallography. 相似文献
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The extended structures of Ag-complexes of the azine based ligands phenyl-2-pyridyl ketone azine (L1) and di-2-pyridyl ketone azine (L2) are reported, and focus is made on the investigation of the influence of the anion and supramolecular interactions on the self-assembly. Using AgNO3, AgClO4 and CF3COOAg salts as starting materials for both ligands in acetonitrile, we observed the formation of the dinuclear complexes [Ag2(L1)2](NO3)2 (1a), [Ag2(L1)2](ClO4)2 (1b), from L1, the tetranuclear complexes [Ag4(L2)2 (NO3)(CH3CN)2](NO3)3 (2a), [Ag4(L2)2(CF3COO)3CH3CN](CF3COO) (2b) and the linear chain polynuclear complex {[Ag3(L2)2] (ClO4)3}n (3) from L2. The X-ray structures show that the molecular geometry depends on the choice of anion. The silver centers have distorted tetrahedral coordination geometry in all the complexes. Weak hydrogen bonding and other interactions result in 2-D and 3-D networks in these complexes. 相似文献
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