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71.
E. P. Olekhnovich S. L. Boroshko Yu. N. Tkachenko A. F. Pozharskii E. B. Tsupak Yu. A. Zhadanov L. P. Olekhnovich 《Russian Chemical Bulletin》1998,47(8):1553-1560
The one-pot method for the synthesis of 4,8-dialkoxy-6-aryl-1,3-dimethylcyclohepta [c]furanium perchlorates has been developed. The method is based on the cyclocondensation of 3,4-diacetylhexane-2,5-diones with
aromatic aldehydes and trialkyl orthoformates under the action of a 16% perchloric acid solution in acetic anhydride. Under
similar conditions, with hydrogen sulfide, cyclohepta[c]thiophenium perchlorates have been obtained, while cyclohepta[c]pyrrolium perchlorates have been prepared with arylamines, ammonium acetate, or aliphatic amine acetates. A heteroanalog
of azulene, 4,8-diethoxy-1,3-dimethyl-2-azaazulene, has been obtained for the first time. Hydrolysis of aza- and thiaazulenium
salts gives the corresponding cyclohepta[c]pyrrol-4-ones and cyclohepta [c]thiophen-4-ones.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1596–1603, August, 1998. 相似文献
72.
N. A. Orlova F. A. Zhuravlev V. V. Shelkovnikov T. N. Gerasimova 《Russian Chemical Bulletin》1995,44(6):1084-1086
A new method for synthesis of 1-[(2-acryloyloxyethyl)- and 1-[(2-propenyl)-2-(2-(1H)-quinolidene)-methyl]-1-ethylquinolinium iodides was proposed. The structures of the dyes obtained were studied by1H NMR spectroscopy.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1122–1124, June, 1995.This work was supported by the Russian Foundation for Basic Research (Project No. 93-02-3467) and the International Science Foundation (Grant RCO 000). 相似文献
73.
V. N. Nesterov I. A. Aitov Yu. A. Sharanin Yu. T. Struchkov 《Russian Chemical Bulletin》1996,45(1):164-167
The reaction of 1-allyl-4-methylquinolinium bromide with 2-dicyanomethyleneindan-1,3-dione in the presence of a two-fold excess of triethylamine affords 1-allyl-4-[2-cyano-2-(indan-1,3-dione-2-ylidene) ethylidene]-1,4-dihydrogtiinoline, a representative of a new class of merocyanines. The structure of this compound has been established by X-ray structural analysis. A substantial intramolecular charge transfer and a hydrogen bond between the vinyl hydrogen atom and the indandione oxygen atom have been found.Dedeased in 1995Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 173–176, January, 1996. 相似文献
74.
Heats of solution of acetonitrile, solvated or hydrated perchlorates, Mn(ClO4)2·6AN, Co(ClO4)2·6AN, Ni(ClO4)2·6AN, Cu(ClO4)2·4AN, Cu(ClO4)2·6H2O, Zn(ClO4)2·6AN, and Zn(ClO4)2·6H2O have been determined in NMF, DMF, DMA, and water. Complete or almost complete exchange of AN and water molecules in amides is inferred from the visible spectra determinations. The heats of transfer of perchlorate anion from water to DMA and NMF have been obtained from separately determined heats of solution of NaBPh4, AsPH4Cl·H2O, NaClO4, NaCl, and SiPh4 in the respective solvents. The heats of transfer of cations from water to amides have been determined from the above data and the heats of solvation of cations using literature data for the heats of hydration. 相似文献
75.
Complexes of lanthanide perchlorates with 4-cyano pyridine-1-oxide, 4-chloro 2-picoline-1-oxide and 4-dimethyl-amino 2-picoline-1-oxide
have been isolated for the first time and characterized by analysis, conductance, infrared, NMR and electronic spectra. The
complexes of 4-cyano pyridine-1-oxides have the composition Ln(CyPO)6(ClO4)3. 2H2O (Ln=La, Sm, Dy and Ho); Ln(CyPO)7 (ClO4)3. 2H2O (Ln=Pr, Nd, Er and Yb); and Ln(CyPO)5 (ClO4)3. 2H2O (Ln=Gd and Tb). The complexes of 4-chloro 2-picoline-1-oxide analyse for the formulae Ln(CpicO)6 (ClO4)3 (Ln=La, Pr, Nd and Ho); and Ln (CpicO)5 (ClO4)3 (Ln=Er and Yb), and those of 4-dimethylamino 2-picoline-1-oxide for Ln(DMPicO)6 (ClO4)3 (Ln=La and Nd); Ln(DMPicO)7 (ClO4)3 (Ln=Gd, Er and Yb); and Ln(DMPicO)8 (ClO4)3 (Ln=Dy and Ho). 相似文献
76.
A. D'aprano B. Sesta V. Mauro M. Salomon 《Journal of inclusion phenomena and macrocyclic chemistry》1999,35(3):451-465
A new method is presented for the analysis of precise conductance data to obtain the true thermodynamic formation constants of macrocyclic–cation complexes. The method, based on the Lee–Wheaton theory on mixed electrolytes, takes into consideration the ion pair formation of both the uncomplexed and complexed cations and avoids the use of the simple additivity assumption of the conductances of two electrolytic species present in salt/ligand/solvent systems. The method has been applied to determine the thermodynamic complexation constants of lithium, sodium and potassium ions with the cryptands [221], [222] and their decyl derivatives [221D], [222D] in acetonitrile. The results show that the presence of an alkyl chain in the molecular structure of the cryptands decreases the macrocyclic–cation complexation constant with respect to the values obtained for the parent compounds by almost an order of magnitude. Such a finding has been explained in terms of the asymmetric position in the space of the oxyethylenic bridges of the macrocyclic ligand promoted by the presence of the linked hydrocarbon chain. The above explanation has been confirmed by the anomalous behavior of both the ion-pair association constants of complexed salts and their limiting molar conductivity. 相似文献