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1.
Thermal van Alphen–Hüttel rearrangement of methyl 3,3-diphenyl-3H-pyrazole-4-carboxylate, 3,3-diphenyl-3H-pyrazole-4-carbonitrile, and methyl 5-methyl-3,3-diphenyl-3H-pyrazole-4-carboxylate involves completely regioselective migration of one phenyl group from the 3-position to N2 with formation of aromatic 1H-pyrazole system. Thermal rearrangement of methyl 3,3-diphenyl-3H-pyrazole-5-carboxylate leads to the formation of methyl 4,5-diphenyl-1H-pyrazole-3-carboxylate as a result of migration of the 3-phenyl group exclusively to the C4 atom and subsequent prototropic isomerization. Under analogous conditions, methyl 4-methyl-3,3-diphenyl-3H-pyrazole-5-carboxylate, methyl 5-(methanesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carboxylate, methyl 5-(benzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carboxylate, and dimethyl 3,3-diphenyl-3H-pyrazole-4,5-dicarboxylate have been regioselectively converted into the corresponding 4H-pyrazoles. Thermolysis of 5-(4-methylbenzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carbonitrile gives rise to a mixture of 1H- and 4H-pyrazoles, the former considerably prevailing, whereas the corresponding 1H-pyrazoles are formed as the only product from 5-(methanesulfonyl)- and 5-(benzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carbonitriles.  相似文献   

2.
Methyl 3-aroyl-1-aryl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates reacted with arylhydrazines to give methyl 3-aroyl-1-aryl-2-(2-arylhydrazinyl)-4-hydroxy-5-oxo-2,5-dihydro-1H-pyrrole-2-carboxylates which underwent thermal recyclization into isomeric methyl 1-aryl-5-(arylcarbamoyl)-4-aroyl-1H-pyrazole- 3-carboxylates and methyl 1,5-diaryl-4-[2-oxo-2-(arylamino)acetyl]-1H-pyrazole-3-carboxylates.  相似文献   

3.
3,5-Dimethyl-1H-pyrazolide of 3-O-acetyl ursolic acid (II) is obtained in the course of the interaction of 3 O-acetyl ursolic acid acyl chloride (I) and 3,5-dimethyl-1H-pyrazole. The crystal structure of compound II is determined from the single crystal XRD data (150 K, Bruker X8 Apex CCD autodiffractometer, MoK α radiation). The crystals are rhombic, the unit cell parameters are as follows: a = 10.6034(2) Å, b = 12.4096(2)Å, c = 24.5972(5)Å, P212121 space group. The structure consists of discrete acentric molecules. When pyrazolide II is boiled in the alcohol alkali solution, secondary hydroxyl is deacetylated and 3,5-dimethyl-1H-pyrazolide of ursolic acid IV is formed. Compounds II and IV are studied by NMR spectroscopy.  相似文献   

4.
The reaction of ethyl 4-formyl-1-phenyl-1H-pyrazole-3-carboxylate with the malonic acid led to the formation (2E)-3-(3-ethoxycarbonyl-1-phenyl-1H-pyrazol-4-yl)propenic acid. In reactions of this acid chloride with 4-amino-5-aryl(hetaryl)-4H-1,2,4-triazole-3-thiols were obtained ethyl 4-[(E)-2-{3-aryl(hetaryl)[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl}ethenyl]-1-phenyl-1H-pyrazoe-3-carboxylates, with 5-aryltetrazoles, ethyl 4-[(E)-2-(5-aryl-1,3,4-oxadiazol-2-yl)-ethenyl]-1-phenyl-1H-pyrazole-3-carboxylates, with 1-(2-hydroxy-3,5-dimethylphenyl) followed by the Baker-Venkataraman rearrangement and the cyclization, ethyl 4-[(E)-2-(6,8-dimethyl-4-oxo-4Hchromen-2-yl)ethenyl]-1-phenyl-1H-pyrazole-3-carboxylate.  相似文献   

5.
Two ethylenediamine derivatives—N-(2-ammoniumethyl)carbamate HN(COO?)CH2CH2N+H3 (I) and tetraacetylethylenediamine (H3CC(O))2NCH2CH2N(C(O)CH3)2 (II) (synthesized for the first time)—have been synthesized and characterized by X-ray crystallography. Compounds I and II are isolated as minor admixtures upon an attempt to synthesize ethylenediamine complexes of lanthanum and neodymium nitrates, respectively. The crystals of I and II are monoclinic: a = 7.778 Å, b = 8.060 Å, c = 7.568 Å, β = 95.73°, Z = 4, space group P21/c (I); a = 5.946, b = 10.255, c = 9.343 Å, β = 95.72°, Z = 2, space group P21/c (II). The bond lengths and bond angles lie within the corresponding standard values. Compounds I and II have different conformations of the N-C-C-N ethylenediamine moiety: gauche in I and trans in II, and the corresponding torsion angles are equal to 66.6° and 180°, respectively.  相似文献   

6.
Double complex salts (DCS) [RuNO(NH3)4(H2O)]2[MCl4]Cl4·2H2O, M = Pt (I) and Pd (II), are prepared and characterized using IR spectroscopy, single crystal and powder X-ray diffraction, and thermogravimetric analysis. Crystalline phases of I and II are isostructural (P2(1)/n space group) and have the following crystallographic characteristics: a = 6.689 Å, b = 15.609 Å, c = 12.348 Å, V = 1289.1 Å3, Z = 2, d x = 2.425 g/cm3 (I) and a = 6.637 Å, b = 15.521 Å, c = 12.244 Å, V = 1261.2 Å3, Z = 2, d x = 2.255 g/cm3 (II). The thermolysis of the obtained DCS in the hydrogen atmosphere affords two-phase mixtures of limited solid solutions of the metals: hcp for ruthenium-based ones and fcc for Pt or Pd based solutions. On decomposition in the helium atmosphere the products contain a minor amount of RuO2. For the phases obtained during thermolysis the parameters are determined and the compositions are estimated. The heating of I to 400°C in the helium-air atmosphere yields a nanocrystalline composite Pt+RuO2 with CSR of ~20 nm.  相似文献   

7.
Structurally related 3H-pyrazoles resulting from 1,3-dipolar cycloaddition of diphenyldiazomethane and 9-diazofluorene to dimethyl acetylenedicarboxylate undergo van Alphen–Hüttel rearrangement on heating in a polar solvent (methanol, ethanol, acetic acid). In the first case, the rearrangement involves strictly regioselective 1,5-phenyl migration toward the carbon atom with the formation of relatively stable 4H-pyrazole. Post-rearrangement of the product on heating at 180°C in toluene gives a mixture of methyl 1H-pyrazole-1-carboxylates via successive migrations of the CO2Me group. In the second case, the aryl substituent concurrently migrates both to nitrogen atom with the formation of 1H-pyrazole structure (phenanthridine derivative) and to carbon atom with subsequent rearrangement of unstable 4H-pyrazole to 3H-pyrazole fused to phenanthrene fragment. Heating of dimethyl acetylenedicarboxylate adducts (3H-pyrazoles) in an aprotic solvent (benzene, toluene) leads to the corresponding denitrogenation products. This process is especially facile for the spirocyclic 3H-pyrazole derived from 9-diazofluorene, and it yields cyclopropene derivative. Some previous errors in the structure determination of the rearrangement products have been corrected.  相似文献   

8.
Two new complexes were synthesized, namely, 7: 2 (2.2.2-cryptand)potassium chloride and (2.2.2-cryptand)ammonium bromide(0.75)chloride(0.25) hydrates: [M(Crypt-222)]+ · Hal? · 3.5H2O, where M = K, Hal = Cl (I) and M = NH4, Hal = Br0.75Cl0.25 (II). The structures of two isomorphous crystals were studied by X-ray diffraction analysis. Trigonal (space group P \(\bar 3\), Z = 2) structures I (a = 11.763 Å, c = 11.262 Å) and II (a = 11.945 Å, c = 11.337 Å) were solved by direct methods and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.057 (I) and 0.065 (II) for all 2626 (I) and 1654 (II) independent measured reflections (CAD-4 automated diffractometer, λMoK α). In structures I and II, the host-guest [M(Crypt-222)]+ complex cation lies on the threefold crystallographic axis and has the approximate D 3 symmetry. In complex I, the coordination polyhedron of the K+ cation (CN = 8) is a bicapped trigonal prism somewhat distorted toward an antiprism. Complexes I and II contain H-bonded disordered cubes of the water molecules and the Cl? or Br? anions.  相似文献   

9.
Three novel 3d–4f heterometal complexes [Ln(NiL)3(Btca)(NO3)] · xH2O (Ln = Sm(III) (I), Pr(III) (II), Eu(III) (III) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien, H2Btca = benzotriazole-5-carboxylic acid) were solvothermally synthesized and characterized by singlecrystal X-ray diffraction (CIF files CCDC nos. 1555557 (I), 1555555 (II), 1555556 (III)). They crystallized in the monoclinic space group P21/n for I (x = 1.5) and C2/c for (II) and (III) (x = 1), respectively. In these complexes, the central Ln(III) and external nickel ions are bridged by macrocyclic oxamide groups. The metal center of Ln(III) resides in a distorted bicapped square antiprism surrounding with six oxygen atoms of three oxamide groups, two oxygen atoms of Btca2– ion and two oxygen atoms of NO3-. Furthermore, there are C–H···O and/or C–H···N hydrogen bond interactions among nitrate, benzotriazole-5-carboxylate, macrocyclic oxamide and water to form three-dimensional superamolecular architecture. The fluorescence properties of the compounds I and II are also discussed.  相似文献   

10.
Compound [VO(acac)2] reacts with the Schiff bases N′-(5-bromo-2-hydroxybenzylidene)-2-hydroxy-3-methylbenzohydrazide (H2Bhm) and 4-bromo-2-[(2-piperidin-1-ylethylimino)methyl]phenol (HBpp) in absolute methanol to give the oxovanadium(V) complexes [VO(Bhm)(OCH3)(CH3OH)] (I) and [VO2(Bpp)] (II), respectively. Both complexes were characterized by elemental analysis, IR spectra, and single-crystal X-ray determination. The crystal of I crystallizes in the triclinic space group \(P\bar 1\) with a = 7.625(2), b = 11.240(3), c = 12.156(4) Å, α = 77.404(5)°, β = 75.770(4)°, γ = 79.922(5)°, V = 977.4(5) Å3, Z = 2. The crystal of II crystallizes in the monoclinic space group P2/c with a = 26.760(3), b = 6.655(1), c = 17.570(2) Å, β = 100.335(2)°, V = 3078.2(7) Å3, Z = 8. The V atom in I is in an octahedral coordination, and those in II are intervenient between square pyramidal and trigonal bipyramidal coordination.  相似文献   

11.
In continuation of a systematic study of bis(citrate)germanates, we synthesized a number of heterometallic germanium(IV) and 3d metal complexes based in citric acid (H4Cit) with the molecular formula [M(H2O)6][Ge(HCit)2] · nH2O, where M = Fe, n = 4 (I); Co, n = 2 (II); Ni, n = 2 (III); Cu, n = 1 (IV); Zn, n = 3 (V). The complexes were characterized by elemental analysis, X-ray diffraction, thermogravimetry, and IR spectroscopy. The X-ray diffraction analysis of compound I was performed. Crystals are monoclinic, a = 10.091(4) Å, b = 11.126(4) Å, c = 10.996(4) Å, β = 100.966(6)°, V = 1212.1(8) Å3, Z = 4, space group P21/n, R1 = 0.0561 for 2266 reflections with I > 2σ(I). Compound I is composed of centrosymmetric octahedral complexes-[Ge(HCit)2]2? anions and [Fe(H2O)6]2+ cations—and crystallization water molecules. Structural units in compound I are combined by a hydrogen bond system.  相似文献   

12.
Two complexes, (2.2.2-cryptand)rubidium chloride and bromide hydrates [Rb(Crypt-222]Hal · 3.5H2O (Hal = Cl (I) and Br (II)), are synthesized. The structures of isomorphic crystals of compounds I and II are studied by X-ray diffraction analysis. The crystals are trigonal: space group P \(\overline 3 \), Z = 2; I: a = 11.810 Å, c = 11.302 Å; II: a = 11.890 Å, c = 11.402 Å. The structures are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.060 (I) and 0.077 (II) for 2650 (I) and 2700 (II) independent reflections (CAD-4 automated diffractometer, λMoK α radiation). In crystals of complexes I and II, the [Rb(Crypt-222)]+ cation of the host-guest type lies on the crystallographic axis 3 and has the approximate symmetry D 3. In complexes I and II, the coordination polyhedron of the Rb+ cation is a two-base-centered trigonal prism somewhat distorted to an antiprism. The crystals of compounds I and II contain H-bonded disordered cubes of the water molecules and Cl? or Br? anions.  相似文献   

13.
A new triazole-substituted ligand H2L (H2Trza = 3-amino-1H-1,2,4-triazole-5-acetate) and its two new isomorphic compounds [M(HTrza)2(H2O)2] ? 2H2O (Co(I) and Mn(II)) have been synthesized and characterized structurally. Their X-ray crystal structures (CIF files CCDC nos. 906893 for I and 906892 for II) show that H2L belongs to a tetragonal system; space group P43 with a = b = 5.0445(13), c = 27.054(10) Å; Z = 4. Complex I belongs to a monoclinic system; space group P21/n with a = 7.6543(8), b = 7.3453(8), c = 13.6283(14) Å; β = 91.5990(10)°, Z = 2. Complex II belongs to a triclinic system; space group with a = 6.8550(15), b = 8.0630(18), c = 15.173(4) Å; α = 84.794(4)°, β = 79.005(3)°, γ = 73.779(4)°, Z = 2. X-ray analysis demonstrates that compound H2L is found to contain a H2Trza and a lattic water molecule; complexes I and II are discrete mononuclear species. The central Co(II) and Mn(II) atoms exhibit octahedral coordinations, type 4 + 2. In two compounds, the coordination entities are further organized via hydrogenbonding interactions to generate uniform supramolecular networks. Thermal stabilities of two compounds were examined by thermogravimetric analysis.  相似文献   

14.
Ethyl 1-aryl-4-acetyl-5-methyl-1H-pyrazole-3-carboxylates reacted with phenylhydrazine to give the corresponding hydrazones, ethyl 1-aryl-5-methyl-4-[1-(phenylhydrazinylidene)ethyl]-1H-pyrazole-3-carboxylates, which were converted to ethyl 1′-aryl-4-formyl-5′-methyl-1-phenyl-1H,1′H-3,4′-bipyrazole-3′-carboxylates by treatment with the Vilsmeier–Haack reagent. No indole derivatives were formed from the same hydrazones under the Fischer reaction conditions, but cyclization to 2-aryl-3,4-dimethyl-6-phenyl-2,6-dihydro-7H-pyrazolo[3,4-d]pyridazin-7-ones was observed.  相似文献   

15.
The syntheses of a mononuclear zinc(II) complex [ZnCl(L1)(Amp)] (I) and a mononuclear nickel(II) complex [Ni(L2)(HL2)](BF4) · 0.5H2O (II) (HL1 = 4-methyl-2-[(4-methylpyridin-2-ylimino) methyl]phenol, HL2 = 4-methyl-2-[(pyridin-2-ylmethylimino)methyl]phenol; Amp = 2-amino-4- methylpyridine) were prepared under microwave irradiation. The complexes were characterized by a combination of elemental analyses, and IR and electronic spectra. Their structures were further confirmed by single crystal X-ray crystallography (СIF files CCDC nos 1437737 (I), 1437738 (II)). The Zn atom in the monomeric complex I is in tetrahedral coordination. The Ni atoms in the dimeric complex II are in octahedral coordination. Crystals of the complexes are stabilized by hydrogen bonds. In order to evaluate the biological activity of the complexes, in vitro antibacterial against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa was assayed. The complexes have strong activity against Bacillus subtilis.  相似文献   

16.
The structure of diastereomeric methyl-7-anti-methoxy-7-syn-phenyl-and methyl-7-syn-methoxy-7-anti-phenyl-6-endo-bromobicyclo[3.1.1]heptane-6-exo-carboxylates 2a and 3a and their chlorine-and iodine-substituted analogs 2b and 3c was studied by XRD. The diastereomers differ in the geometrical parameters of the carbon framework of the molecules. The C(1)-C(2)-C(3)-C(4)-C(5)-C(6) six-membered ring is in the intermediate conformation between envelope and chair in structures 2 and envelope in structures 3. In compound 2a, the cyclobutane fragment has a higher degree of folding than in 3a; one of the possible reasons for that is the donor-acceptor interaction between the 6-methoxycarboxylic and 7-methoxy groups in molecule 2a.  相似文献   

17.
Two complexes, namely, triaqua(18-crown-6)strontium dibromide monohydrate (I) and diaquabromo(18-crown-6)barium bromide (II), are synthesized. Their crystal structures are determined by X-ray diffraction analyses. For complex I, space group C2/c, a = 17.547 Å, b = 10.246 Å, c = 14.786 Å, β = 123.08°, Z = 4. For complex II, space group Pnma, a = 17.753 Å, b = 17.465 Å, c = 6.629 Å, Z = 4. The structures are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.056 (I) and 0.042 (II) for 2696 (I) and 2440 (II) independent reflections (CAD-4 automated diffractometer, λMoK α radiation). Both complex cations—randomly disordered [Sr(18C6)(H2O)3]2+ in complex I and [BaBr(18C6)(H2O)2]+ in complex II—are of the host-guest type. The Sr2+ (Ba2+) cation resides in the cavity of the 18-crown-6 ligand and coordinated by all six O atoms. In the structures complexes I and II, the coordination polyhedra of the Sr2+ and Ba2+ cations (coordination number 9) can be described as distorted hexagonal bipyramids with one apex at the O atom of the water molecule in complex I or at the Br? ligand in complex II and the other split apex at the O atoms of two water molecules.  相似文献   

18.
A procedure was proposed for regioselective acylation of methyl 2-methyl-4H-thieno[3,2-b]-pyrrole-5-carboxylate with 2-(3-indolyl)-2-oxoacetyl chloride. Reactions of the resulting methyl 6-[2-(3-indolyl)-1,2-dioxoethyl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate with aromatic aldehydes and ammonium acetate in acetic acid afforded the corresponding methyl 6-[2-aryl-4-(3-indolyl)imidazol-5-yl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylates. The structure of methyl 6-[2-(4-chlorophenyl)-4-(3-indolyl)imidazol-5-yl]-2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate was studied by X-ray analysis.  相似文献   

19.
Macrocyclic and supermolecular complexes [Cu2(NiL)2Cl4] (I) and [Cd2(CuL)2Cl4] (II) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) have been synthesized and structurally determined by X-ray diffraction and IR spectrum. Complex I crystallizes in the monoclinic system with P21/n group, a = 10.9019(15), b = 14.3589(19), c = 12.4748(17) 0A, β = 108.645(2)°, Z = 4. Complex II crystallizes in the monoclinic system with P21/n group, a = 10.9784(16), b = 14.580(2), c = 12.8904(18) Å, β = 109.339(2)°, Z = 4.  相似文献   

20.
Two new cobalt(III) and zinc(II) complexes, [Co(L1)2 (H2O)] · ClO4 (I) and [Ni(L2)2 (H2O)2] · 2ClO4 (II), where L1 is the deprotonated form of 5-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenol, and L2 is the zwitterionic form of 2-[(2-isopropylaminoethylimino)methyl]-5-methoxyphenol, were synthesized and structurally characterized by elemental analyses, IR spectra, and single-crystal X-ray diffraction. The crystal of I is monoclinic: space group P21/c, a = 11.1512(4), b = 28.2424(11), c = 10.9655(4) Å, β = 95.746(2)°, V = 3436.1(2) Å3, Z = 4. The crystal of II is triclinic: space group P21/c, a = 8.1441(2), b = 10.4531(3), c = 10.8849(3) Å, α = 84.0240(10)°, β = 76.9800(10)°, γ = 74.2280(10)°, V = 867.92(4) Å3, Z = 1. Complex I consists of a mononuclear cobalt(III) complex cation and a perchlorate anion. Complex II consists of a crystallographic centrosymmetric mononuclear nickel(II) complex cation and two perchlorate anions. Each metal atom in the complexes is in an octahedral coordination.  相似文献   

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