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In the title compound, C8H6N4O2, the tetrazole and benzene rings are planar to within 0.001 (1) and 0.007 (1) Å, respectively. These rings are not coplanar in the mol­ecule, the dihedral angle between them being 52.90 (4)°. Molecules are connected together by O—H⋯N and C—H⋯O hydrogen bonds, forming two-dimensional networks parallel to the xz plane with van der Waals interactions between them.  相似文献   

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Reactions of alkyl 4-aminobenzoates with maleic anhydride give the corresponding alkyl 4-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoates, and the latter are converted into 4-(3-dialkylamino-2,5-dioxo-2,3,4,5-tetrahydro-1H-pyrrol-1-yl)benzoates by treatment with secondary amines.  相似文献   

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The use of two oxidoreductases (an aldoketo reductase from Escherichia coli JM109 and an alcohol dehydrogenase from Lactobacillus brevis) has demonstrated that it is possible to prepare enatiomerically pure diols in a one-pot operation. The reactions were applied to the synthesis of (1R)-1-[3-(hydroxymethyl)phenyl]ethanol and (1S)-1-phenylethane-1,2-diol, using a two-step procedure. The yield is nearly quantitative and the enantiomeric purity is greater than 95%. A third step has been introduced by adding a cell biocatalyst showing dihydrodiol dehydrogenase activity from Pseudomonas fluorescens N3. This allows for the preparation of 3-[(1R)-1-hydroxyethyl]benzoic acid and (2S)-hydroxy(phenyl)ethanoic acid.  相似文献   

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Three conformational polymorphs of 3-(azidomethyl)benzoic acid, C8H7N3O2, are reported. All three structures maintain similar carboxylic acid dimers and π–π stacking. Crystal structure analysis and computational evaluations highlight the azidomethyl group as a source of conformational polymorphism, thus having potential implications in the design of solid-state reactions.  相似文献   

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Oxidation of Dichloramine-T with KMnO4 in mild alkaline medium affords N,N-dichlorosulfamoylbenzoic acid (Halazone) in high yield with 18–20% chlorine content.
Eine verbesserte Vorschrift für die Synthese vonp-(Dichlorsulfamoyl)benzoesäure (Halazon) (Kurze Mitteilung)
Zusammenfassung Die Oxidation von Dichloramin-T mit KMnO4 ergab unter mild alkalischen Bedingungen N,N-Dichlorsulfamoylbenzoesäure (Halazon) in hohen Ausbeuten mit einem Chlorgehalt von 18–20%.
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Salt resistivity of poly (4-vinyl benzoic acid) (P4VBA) gel was investigated to compare with the super salt-resistivity that was found for poly (4-vinyl phenol)(P4VPh) gel containing an acidic proton and π-electron system. Poly(acrylic acid) (PAA) gel was also prepared and used as a reference gel containing only an acidic proton. P4VBA gel showed a moderate salt resistivity, which was less significant than that for P4VPh gel, in many kinds of inorganic salt solutions (MgCl2, LiCl, NaCl, KCl, CsCl, KI, KSCN, Na2SO4). On the other hand, PAA gel showed a drastic deswelling in the presence of concentrated MgCl2, LiCl, Na2SO4, and (NH4)2SO4 solutions, and a significant swelling for KSCN solution. These contrastive behaviors between P4VBA and PAA gels strongly suggest that the combination of acidic proton and π-electron system is essential and necessary for polymer gels to be endowed with the salt resistivity.  相似文献   

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Copolyesters of 4-hydroxybenzoic acid (HBA) and 3-(4'-hydroxyphenoxy)benzoic acid were prepared by two different procedures. Either the acetyl derivatives were polycondensed in bulk at temperatures up to 300°C or they were polycondensed in an inert reactions medium (Marlotherm-S) at 340°C. Two analogous series of copolyesters were synthesized from 4-acetoxybenzoic acid (4-HBA) and 4-(3'-acetoxyphenoxy)benzoic acid. The copolyesters were characterized by elemental analyses, inherent viscosities, 1H- and 13C-NMR spectroscopy, WAXS and DSC measurements, and by optical microscopy. All copolyesters synthesized in solution were highly crystalline materials which were neither meltable nor soluble. Part of the copolyesters prepared by polycondensation in bulk were semi-crystalline, meltable, and soluble. The copolyester derived from 3-(4'-hydroxyphenoxy)benzoic acid proved to be thermotropic forming a nematic melt, whereas the isomeric copolyesters of 4-(3'-hydroxyphenoxy)benzoic acid only formed isotropic melts. © 1993 John Wiley & Sons, Inc.  相似文献   

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Ultraviolet irradiation of a salt crystal of 4-(2,4,6-triisopropylbenzoyl)benzoic acid with (S)-phenylethylamine promoted single-crystal-to-single-crystal photocyclization to give an enantiopure (R,R)-cyclopentenol and almost racemic cyclobutenol. The reaction paths were elucidated by X-ray crystallographic analysis of the crystal before and after irradiation.  相似文献   

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Yttrium complexation in extraction systems with benzoic acid (BA) and tris(hydroxymethyl)aminomethane (THMAM) was studied. The growth of yttrium distribution ratios in this system is caused by the formation of different-ligand coordination compounds of yttrium with BA and THMAM. Quantum chemical calculations for the formation energy of different-ligand complex showed that the most stable complex forms when yttrium atom coordinates to two THMAM molecules via oxygen and nitrogen atoms and to one THMAM molecule via nitrogen atom. The complex is stable in both bidentate and monodentate coordination of the carboxyl groups of benzoic acid to yttrium atom. Obtained yttrium extracts were used for the synthesis of complex-oxide nanosized cathodophosphors by extraction-pyrolytic technique.  相似文献   

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An efficient synthesis of 4-(1-adamantyl)benzoic acid based on transition metal ion catalyzed oxidation of 4-(1-adamantyl)toluene has been developed. As a catalytic system, cobalt-manganese bromide with addition of manganese acetate was used. A series of amino acid derivatives of 4-(1-adamantyl)benzoic acid was then synthesized and characterized. These derivatives are novel intermediates potentially useful in the design of therapeutically active peptidomimetics with improved pharmacokinetic and pharmacodynamic parameters.  相似文献   

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The AB2 monomer, 3,5-bis(3-hydroxylprop-1-ynyl)benzoic acid 1, has been synthesized using a Sonogashira cross-coupling with a palladium catalyst system developed for use with deactivated aryl halides. Numerous condensation methods have then been assessed in the homopolymerization of the acid-diol monomer 1 to afford hyperbranched polyesters. However, as a result of the thermal instability of the monomer, direct thermal polymerizations could not be employed. Alternative approaches using carbodiimide-coupling reagents enabled the production of soluble polyesters possessing molecular weights and degrees of branching ranging from 2500 to 11,000 and 0.22 to 0.33, respectively.  相似文献   

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The title compounds, 4‐(diiodoarsanyl)benzoic acid, (I), and 3‐(diiodoarsanyl)benzoic acid, (II), both [As(C7H5O2)I2], which possess a –COOH coordinating group, form molecular crystal structures composed of hydrogen‐bonded dimers, the packing differences of which are caused by the relative position of the diiodoarsanyl groups. The para isomer, with Z′ = 1, crystallizes in a layered structure with shortened contacts of the As atoms to only the arene rings of adjacent molecules. In contrast, the meta isomer, with Z′ = 3, forms separate rectangular blocks of three ribbons, each composed of dimeric molecular units positioned almost directly above each other and with the As atoms possessing only two As...I contacts to the I atoms of neighbouring molecules.  相似文献   

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4-(1H-imidazol-1-yl) benzoic acid and its coordination polymers [M(IBA)Cl] n (M?=?Zn (1) and Co (2)) have been synthesized. Compounds 1 and 2 were obtained under ionothermal conditions and possess a 2-D laminar [M(IBA)] n layer based on M2(CO2)2 building blocks with coordinated chloride completing tetrahedral coordination of the metal. Compound 1 exhibits two photoluminescence emission peaks at 410 and 510?nm. The low-energy emission can be attributed to ligand-centered transition and the high-energy band can be assigned to ligand-to-metal charge transfer between the aromatic systems of the organic ligands and the 4s orbitals of Zn(II). The role of the ionic liquid in ionothermal synthesis and crystallization of 1 and 2 are briefly discussed.  相似文献   

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The esterificaion of benzoic acid has been studied in an experimental, isothermal, semi-batch reactor using sulfuric acid catalyst. The reaction appears to be the first order with respect to benzoic acid and does not depend on the concentration of octyl alcohol. The kinetic parameters are given. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

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