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1.
é. I. Ivanov A. A. Polishchuk S. M. Avraamov R. Yu. Ivanova 《Chemistry of Heterocyclic Compounds》1989,25(1):29-32
It is shown that the reaction of tetranitrodibenzo-18-crown-6 with sodium alkoxides in aprotic solvents at room temperature occurs with initial cleavage of the macroheterocycle and formation of an intermediate — substituted o-dinitrobenzene — whereas the reaction in protonated solvents occurs with substitution of the nitro groups. From among other derivatives of dibenzo-18-crown-6 containing azole rings linked to the benzene ring, only the furoxan-containing crown ether is cleaved under similar conditions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 37–40, January, 1989. 相似文献
2.
The nature of the reaction of a reagent with tetranitrodibenzo-18-crown-6 was found to depend on its basicity. This behavior was interpreted in the framework of the theory of hard and soft acids and bases.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 605–608, May, 1992. 相似文献
3.
N. Zh. Saifullina K. A. Ibragimzhanov A. K. Tashmukhamedova Kh. M. Shakhidoyatov 《Chemistry of Heterocyclic Compounds》1999,35(7):821-824
The condensation of (benzo-15-crown-5)-4-thiocarboxamide with anthranilic acid is studied for the first time. Novel representative of crown ethers incorporating the quinazoline moiety is synthesized. Methylation of (benzo-15-crown-5)-4-thiocarboxamide proceeds anomalously giving (benzo-15-crown-5)-4-carbonitrile. (Benzo-15-crown-5)-4-thiocarboxamide is reacted with thioveratramide in order to compare the reaction paths.Mirzo Ulugbek Tashkent State University, Tashkent 700095, Republic of Uzbekistan; Institute of Plant Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent 700170. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 937–940, July, 1999. 相似文献
4.
O. A. Raevskii V. V. Tkachev V. P. Kazachenko A. N. Razdol'skii I. I. Bulgak V. E. Zubareva 《Russian Chemical Bulletin》1989,38(4):748-753
1. | An x-ray structure analysis has revealed substantial diferrences in the conformational states of 2,3-(4-benzoyl)benzo-15-crown-5 and benzo-15-crown-5 in the crystal phase, differences related to realization of a trans-gauche-gauche' conformation in one COCCOC fragment in the 2,3-(4-benzoyl)benzo-15-crown-5. |
2. | In nonpolar solvents, an equilibrium of several structures is realized in both compounds, an equilibrium with the participations of trans-gauche-trans, trans-gauche-gauche and trans-gauche-gauche' conformations. In a polar medium, there are no indications of the trans-gauch-gauche' conformation. |
3. | Upon complexation of the ligands with calcium thiocyanate in acetonitrile, there are spectral indications of complexes with differing stoichiometry, with a large contribution of the structure from trans-gauche-trans conformations. |
5.
Janusz Wasilewski Jan F. Biernat 《Journal of inclusion phenomena and macrocyclic chemistry》1991,10(1):109-118
Lipophilic bis-substituted ester and ether derivatives of benzo-15-crown-5 have been synthesised. The correlation between the structure and potentiometric ion-selectivity has been studied in PVC membrane ion-selective electrodes. An ion-selective potassium sensitive electrode based on 4,5-bis (biphenyloxymethyl)benzo-15-crown-5 exhibited the best electrode properties. The detection limit was loga
K = -5.4; logK
K,Na
ppot = -3.5. The effect of the lipophilicity of neutral carriers upon electrode performance has been also discussed. 相似文献
6.
William H. Watson Prem C. Jain 《Journal of inclusion phenomena and macrocyclic chemistry》1986,4(4):397-405
Benzo-15-crown-5 and thiooxamide in the 11 complex form infinite chains of alternating host-guest molecules. The host oxygen atoms are involved in six close interactions with amide hydrogen atoms forming one bifurcated and one single hydrogen interaction on each face. In the 12 complex the host forms a distinct molecular entity with two thioacetamide molecules. Again one bifurcated and one normal hydrogen...oxygen interaction occurs on each face. The conformation of the benzo-15-crown-5 host is the same in both complexes and agrees with a conformation of the free host calculated by molecular mechanics. The conformation of crystalline benzo-15-crown-5 differs from that calculated. In either case, no major conformational reorganization is required to accommodate the intermolecular interactions. The oxygen atoms of the benzo-15-crown-5 form an approximate pentagon with the amide nitrogen atoms lying 2.18(1) Å from the mean plane.
Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82041 (43 pages). 相似文献
7.
Chromogenic benzo-12-crown-4, benzo-13-crown-4 and benzo-14-crown-4 ethers have been compared with monoaza-12-crown-4 and monoazal-13-crown-4 ethers. Of these compounds, monoaza-13-crown-4 exhibited the best analytical characteristics toward the selective determination of lithium. K(ex)Li/K(ex)Na was 525 for the monoaza-crown-4 compound. 相似文献
8.
Chuanju Zhang 《Tetrahedron letters》2008,49(48):6917-6920
Pyrido-21-crown-7 (P21C7) has been synthesized and shown to form [2]pseudorotaxanes spontaneously with secondary dialkylammonium ions. These complexes are stronger than their benzo-21-crown-7 counterparts and much stronger than their dibenzo-24-crown-8 counterparts. Based on this new P21C7/secondary dialkylammonium salt recognition motif, a [2]rotaxane terminated by phenyl groups as stoppers has been successfully constructed using the threading-followed-by-stoppering technique. 相似文献
9.
D. Kh. Aslanova A. K. Tashmukhamedova R. R. Razakov 《Chemistry of Heterocyclic Compounds》1987,23(7):737-740
The mass spectra of 4-acyl derivatives of benzo-15-crown-5 and benzo-18-crown-6 were studied by the method of direct analysis of the daughter ions (DADI). It was established that the fragmentation of the M+ ions of the investigated compounds under electron impact proceeds via the scheme of the McLafferty rearrangement with the simultaneous elimination of ethylene oxide. The degree of occurrence of the McLafferty rearrangement increases with an increase in the length of the side chain.See [3] for communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 989–901, July, 1987. 相似文献
10.
Yu Liu Hong Wang Zhi-Hui Zhang Bao-Zhi Tian Shu Huang 《Journal of inclusion phenomena and macrocyclic chemistry》1999,34(2):189-197
Spectrophotometric titrations performed in anhydrous acetonitrile at 25°C give the complex stability constants (log Ks) and the Gibbs free energy changes (-G° for the stoichiometric 1 : 1 intramolecular sandwich complexation of light lanthanoid (III) nitrates (La Gd) with the polymethylene-bridged bis(benzo-12-crown-4)s 1, the corresponding dioxo derivative 2 and its dihydroxy analogue 3. The complex stability sequence as a function of reciprocal ionic radius of lanthanoids showed similar profiles in stability constants (log Ks) and maximum stabilities were obtained at Eu3+ for the complexation of light lanthanoids with the three bis(benzo-12-crown-4)s 1–3. The cation binding abilities and relative selectivities for the trivalent lanthanoid ions of these structurally related bis(benzo-12-crown-4)s 1–3 are discussed according to the derivatization of the bridging. 相似文献
11.
E. Luboch A. A. Dvorkin Yu. A. Simonov 《Journal of inclusion phenomena and macrocyclic chemistry》1994,20(4):335-351
Lipophilic derivatives of benzo-12-crown-4 and naphtho-12-crown-4 have been synthesized. The behavior of the parent compounds and their derivatives in membrane ion-selective electrodes have been studied. Selectivity changes have been observed with the rise in lipophilicity. Crystal structures of the NaI and KI complexes of benzo-12-crown-4 (1 and2) have been determined by X-ray analysis. The alkali metal and iodide ions are in direct contact in2 but not in1. Compound1 [Na(benzo-12-crown-4)2]·I is triclinic, witha=13.368(8),b=10.727(7),c=10.325(4) Å; =73.56(4),=77.73(4), =108.70(5)°;Z=2, space group is
. Compound2 [K(benzo-12-crown-4)2·I] is monoclinic, witha=15.807(8),b=12.043(4),c=15.601(6) Å,=117.74(3)°;Z=4, space groupC2/c. In both compounds the cations interact with all oxygen atoms of two crown ether molecules. Correlation of the crystal structures and behavior of the crown ethers in ion-selective membrane electrodes is discussed.
Supplementary Data related to this article have been deposited with the British Library as Supplementary Publication No. 82185 (15 pages). 相似文献
12.
Crystalline [Y(OH2)3(NCMe)(benzo-15-crown-5)][ClO4]3·benzo-15-crown-5-CH3CN can be obtained by slowly cooling a reaction mixture of Y(ClO4)3·n H2O with benzo-15-crown-5 in a solution of acetonitrile and methanol (3 : 1) from 60°C to room temperature. The crystal structure of this complex has been determined at –150 and 20°C. The complex is triclinic,P
. At –150°C the cell parameters area = 11.986(4),b = 12.071(7),c = 16.364(5) Å, = 93.56(3), = 98.68(3), = 109.68(4)°, vol = 2187 Å3, andD
calc = 1.61 g cm–3 forZ = 2 formula units. 3633 independently observed [F
o 5(F
o)] reflections were used in the final least-squares refinement leading to an agreement index ofR = 0.048. The Y(III) ion coordination geometry approximates a tricapped trigonal prism with three water molecules and three benzo-15-crown-5 oxygen atoms forming the prism, with the two remaining benzo-15-crown-5 oxygen atoms and the acetonitrile molecule completing the coordination as capping atoms. The three water molecules hydrogen bond a second crown ether molecule and two of the perchlorate anions. The two acetonitrile molecules have contacts with perchlorate oxygen atoms close enough for some weak interaction. One perchlorate is ordered, one is partially disordered as is the coordinated solvent molecule, and the third anion is totally disordered. The two unique crown ether molecules have distinctively different conformations.For Part 20, see reference [1]. 相似文献
13.
Reactions of 4"-iodobenzo-15-crown-5 ether with ethynylarenes or 4"-ethynylbenzo-15-crown-5 ether with haloarenes in the presence of catalytic amounts of PdIIcomplex salts, CuI, and Et3N gave 4"-(arylethynyl)benzo-15-crown-5 ethers in 55—80% yields. 相似文献
14.
Bis-crown ethers with benzo-15-crown-5 and benzo-18-crown-6 moieties bridged by different length of polyethylene ethers have been successfully synthesized. 相似文献
15.
From extraction experiments with 133Ba as a tracer, the extraction constant corresponding to the equilibrium Ba2+(aq) + 2A-(aq) + 2L(nb) BaL2
2+(nb) + 2A-(nb) in the two-phase water-nitrobenzene system (A- = picrate, L = benzo-15-crown-5; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K
ex (BaL2
2+, 2A-) = 5.7. Furthermore, the stability constant of the benzo-15-crown-5 - barium complex in nitrobenzene saturated with water was calculated: log bnb (BaL2
2+) = 14.6. 相似文献
16.
The molecular structures of (benzoyl)benzo-12-crown-4 (a=22.387,b=4.503,c=16.167 Å,d
calc=1.34 g cm–3,Z=4, space groupP21
nc, DAR-UM, Cu-K,R=0.056) and (diphenylacetyl)benzo-12-crown-4 (a=8.866,b=23.337,c=10.737 Å;d
calc=1.25 g cm–3,Z=4, space groupP212121, DAR-UM, Cu-K, R=0.056) have been investigated. The differences in the conformations of the macrocycles and the degree of conjugation between the benzene ring orbitals and the lone pairs on the adjacent oxygen atoms in the macrocycle are discussed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1906–1911, November, 1993. 相似文献
17.
Jan F. Biernat Andrzej Cygan Elzbieta Luboch Yurii A. Simonov Tadeush I. Malinovski Vitalii K. Bel'skii Nadezda F. Bolotina 《Journal of inclusion phenomena and macrocyclic chemistry》1993,15(4):369-383
The structure of the trichlorocuprate of naphtho-15-crown-5 complexed potassium has been determined by X-ray analysis. The crystal contains the complex cations [K(naphtho-15-crown-5)2]+, the anion [Cu2Cl6]2– and water molecules. The full composition of the compound in the solid state is represented by the formula [K(naphtho-15-crown-5)2]2[Cu2Cl6]·nH2O), wheren3. The sandwich type cations are similar to those found previously for potassium complexes with benzo-15-crown-5. The coordination number of potassium is equal to 10; the coordination polyhedron is a 15-crown-5. The coordination number of potassium is equal to 10; the coordination polyhedron is a pentagonal antiprism. The water molecules are disordered and occupy six symmetrically independent positions with a probability of 0.5 in the crystal. The lack of close contacts between water molecules and the remaining components enabled the treatment of the complex as a clathrate.
Supplementary Data relating to this article has been deposited with the British Library as Supplementary Publication No. 82154 (20 pages). 相似文献
18.
Yurii A. Simonov Alexandr A. Dvorkin Marina S. Fonari Tadeush I. Malinowski Elżbieta Luboch Andrzej Cygan Jan F. Biernat Edward V. Ganin Yurii A. Popkov 《Journal of inclusion phenomena and macrocyclic chemistry》1993,15(1):79-89
The crystal structures of two 12-membered crown ethers, benzo-12-crown-4 (1) and naphtho-12-crown-4 (2), have been determined by X-ray analysis. Both structures are molecular. Compound1 is monoclonic,P21/b,a=8.466(3),b=8.019(3),c=33.590(10) Å, =90.99(3)o. The unit cell contains two crystallographically independent molecules of1 with similar conformations. Compound2 is also monoclinic,P21/a,a=24.148(8),b=14.535(4),c=7.987(5) Å, =102.87(2)o. Two independent molecules in the unit cell have significantly different conformations.
Supplementary data relating to this publication have been deposited with the British Library as Supplementary Publication No. SUP 82145 (19 pages). 相似文献
19.
Yangjie Wu Haoyun An Jingchao Tao Jerald S. Bradshaw Reed M. Izatt 《Journal of inclusion phenomena and macrocyclic chemistry》1990,9(3):267-274
Complexes of nine 4'-substituted benzo-15-crown-5 ligands with sodium picrate were prepared. A good linear relationship of the . values from the UV spectra and Hammett [p - m] values was observed. Charge transfer complexes of ten 4'-substituted benzo-l5-crown-5 ligands with picric acid were isolated in crystalline form. The color of the complexes depended on the nature of the substituents. All of the complexes were identified by elemental analyses, UV and IR spectra. 相似文献
20.
Yu. A. Plachev A. Yu. Chernyadyev A. Yu. Tsivadze 《Russian Journal of Inorganic Chemistry》2009,54(4):558-562
The reaction of meso-tetra(benzo-15-crown-5)porphyrin (H2TCP) with the osmium carbonyl complex Os3(CO)12 yieds the corresponding osmium(II) porphyrinate OsTCP(CO). The oxidation of OsTCP(CO) with air oxygen and hydrogen peroxide in neutral and acidic media was studied. A preparative method for the synthesis of osmium(VI) meso-tetra(benzo-15-crown-5)porphyrinate (OsO2) TCP by the oxidation of OsTCP(CO) with 50% hydrogen peroxide in acetic acid was developed. The structures of new osmium porphyrinates were determined by IR, 1H NMR, and UV/Vis spectroscopies. 相似文献