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1.
4-Hydroxy-2 H-chromen-2-one and 4-hydroxy-2 H-chromene-2-thione reacted with allyl bromide, 1,1,3-trichloroprop-1-ene, and 1,3-dichlorobut-2-ene to give the corresponding ethers, which were oxidized to (2-oxo-2 H-chromen-4-yloxy)acetic acid with potassium permanganate, and various derivatives of that acid were obtained. 3-(3,3-Dichloroprop-2-enyl)-7-hydroxy-4-methyl-2 H-chromen-2-one and 3-(3,3-dichloroprop-2-enyl)-7-hydroxy-4-methyl-2 H-chromene-2-thione were synthesized, and some their transformations were studied. 相似文献
2.
The reaction of 2 formyldimedone with 2-amino- and 2-hydrazinobenzimidazoles at 20°C in ethanol gave 2-(2-benzimidazolyl)aminomethylene- and 2-[2-(2-benzimidazolyl)hydrazinomethylene]-5,5-dimethylcylohex-anediones, while this reaction carried out in ethanol at reflux in the presence of acid gave 2,2-dimethyl-4-oxo 1, 2, 3, 4-tetrahydroquinazolino(1, 2- a]benzimidazole and 1-(2-benzimidazolyl)-6, 6-dimethyl-4-oxo-4, S, 6, 7-tetrahydroindazole, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 247–252, February, 1996. 相似文献
3.
Summary The ability of [MoS 4] 2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe 2+. The present study has been restricted to linear complexes such as (NEt 4) 2 [Cl 2FeS 2MoS 2] and (NEt 4) 2[Cl 2FeS 2MoS 2FeCl 2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS 2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl 2] 2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl 4Fe 2MoS 4] 2–[Cl 2FeMoS 4] 2–+FeCl 2. The equilibrium constant, K D, was evaluated by differential pulse polarography. K D is tightly related to the donor number of the solvent. 相似文献
4.
Ten new dimeric organotin compounds {[(ArCH 2) 2 Sn(2‐quin)] 2O} 2 (Ar = Ph 1 , 2‐ ClC 6H 4 2 , 3‐ ClC 6H 4 3 , 4‐ ClC 6H 4 4 , 2‐FC 6H 4 5 , 3‐FC 6H 4 6 , 4‐FC 6H 4 7 , 4‐BrC 6H 4 8 , 4‐CNC 6H 4 9 , 2,4‐Cl 2C 6H 3 10 ) have been synthesized by dealkylation reactions of 2‐quinH with [(ArCH 2) 3Sn] 2O, and their structures have been characterized by elemental analysis, IR and NMR ( 1}H, 13C, 119Sn) spectroscopies. The structures of {[(2‐ ClC 6H 4CH 2) 2Sn(2‐quin)] 2O} 2 2 have been determined by X‐ray diffraction. Studies show that compound 2 has a tetranuclear, centrosymmetric dimeric structure, with the endo‐cyclic tin atom five‐coordinated and the exo‐cyclic tin atom six coordinated. Studies also show that the nitrogen atoms of the 2‐quin ligand are coordinating to the tin atom for all the ten compounds. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:152–159, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20194 相似文献
5.
Chlorosulfonyl isocyanata (CSI) reacts with 2H-azirines 1 a-c at -78°C to form [2+2+2] cycloadducts 3a-c and 4a-c. The tricyclic aziridine derivatives 4a-c undergo CSI extrusion reactions and subsequent oxidation to the corresponding pyrazines 5a-c. Structural identifications of 3a-c and 4a-c are based on ir, nmr and mass spectral data. 相似文献
6.
Reaction of NCC 6H 4X-4 (X Me, OMe, or Cl) with trans-[ReCl(N 2)(dppe) 2] (dppe Ph 2PCH 2CH 2PPh 2), at room temperature, in the presence of Tl[BF 4], gives the corresponding complexes cis-[Re(NCC 6H 4X-4) 2(dppe) 2][BF 4] ( 1); the crystal structure of 1 (X Me) has been determined by single crystal X-ray diffraction analysis. 相似文献
7.
As a possible important intermediate during the oxidation of toluene in gas phase, the PhCH2O4CH2Ph molecule has been invested on the structural parameters at CAM-B3LYP/6-311+g(df,pd) level, the vibrational frequencies at B3LYP-D3(BJ)/6-311+g(df,pd) level, and the potential energy surface of isomerization between main isomers at CCSD(T)-F12/cc-pVDZ-F12 level of theory. Ten PhCH2O4CH2Ph isomers were located, in which the structural parameters of C-O4-C skeleton are close to those in HO4H and C2H5O4C2H5. However, due to larger steric hindrance of aromatic groups, PhCH2O4CH2Ph has a more open geometry with larger bond angles and dihedral angles in individual isomers. Meanwhile, it seems that the hyperconjugation appears to be stronger between the O-O bonds and aromatic groups, since the O-O bond lengths are slightly shorter than those found in HO4H and C2H5O4C2H5. Harmonic vibrational frequencies of PhCH2O4CH2Ph isomers were first reported here and we found that the frequencies of O4 torsion and O-O/C-O stretches in PhCH2O4CH2Ph are consistent with those of CH3O4CH3 and C2H5O4C2H5. In the progress of isomerization, three transition states were located and a thermodynamic equilibrium between three main isomers may achieve at ambient temperature concerning the characters of energy barrier. 相似文献
8.
Conclusions The product of conversion of O-bis(2-fluoro-2,2-dinitroethyl)nitromethylbis(2-fluoro-2,2-dinitroethyl)carboxime in methanol or ether is O-bis(2-fluoro-2,2-dinitroethyl)nitromethyl-2-fluoro-2,2-dinitroethyl-2'-fluoro-2-nitroethylenecarboxinie, the structure of which has been established by x-ray diffraction analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2019–2021, September, 1987. 相似文献
9.
The dehydration of Mg(H 2PO 4) 2·2H 2O was investigated by means of thermal analysis, X-ray diffraction, IR absorption and chromatographic methods. The dehydration process and the structures of the products were found to depend considerably on the water vapor partial pressure in the gas phase. Therefore, in thermal analysis, the sample holder type had an analogous influence on the results. The dehydration end-product at 550 °C when the labyrinth crucible was used was well-crystallized Mg(PO 3) 2, whereas with the multiplate sample holder it was completely amorphous condensed magnesium phosphate.
Zusammenfassung Mittels Thermoanalyse, Röntgendiffraktion, IR-Absorptionsspektroskopie und chromatografischen Methoden wurde die Dehydratation von Mg(H2PO4)2·2H2O untersucht. Es wurde festgestellt, daß der Dehydratationsvorgang und die Struktur der Produkte beträchtlich vom partiellen Dampfdruck von Wasser in der Gasphase abhängen. Der Probenhaltertyp in der Thermoanalyse besitzt deshalb einen analogen Einfluß auf die Ergebnisse. Wird ein Labyrinthtiegel verwendet, ist das Dehydratationsendprodukt bei 550 °C kristallines Mg(PO3)2, bei der Verwendung eines Mehrplattenprobenhalters hingegen erhält man amorph kondensiertes Magnesiumphosphat.
Mg(H2PO4)2·2H2O , , - . , , , () . , 550 °C Mg(PO3)2, . 相似文献
10.
The cyclization at the treatment of acetic anhydride of 4-aryl-2-arylamino-4-oxobut-2-enoic and 2-arylamino-5,5-dimethyl-4-oxohex-2-enoic acids was investigated furnishing derivatives of 5-aryl-3-aryl-imino-3 H-furan-2-ones and 4-arylamino-2- tert-butyl-2,5-dihydro-5-oxofuran-2-yl acetate respectively. 2-N 2-Methylenesubstituted 4-aryl-2-hydrazino-4-oxobut-2-enoic and 5,5-dimethyl-2-hydrazino-4-oxohex-2-enoic acids cleanly underwent cyclization under the effect of acetic anhydride into 5-aryl-3-hydrazono-3H-furan-2-ones and 5- tert-butyl-3-hydrazono-3 H-furan-2-ones. 相似文献
11.
The crystal structure of [Nb 2(S 1.72Se 2.28)(S 2CNEt 2) 4], which is a solid solution based on [Nb 2(μ 2, η 2-X 2) 2(S 2CNEt 2) 4], where X 2=S 2, SSe, and Se 2, is determined. The compound was obtained by the reaction of NaS 2CNEt 2 in CH 3CN with the product of the reaction of the NbSe 2Cl 2-KNCS fusion cake with an aqueous solution of Bu 4NBr (yield 30%). The crystals are monoclinic, a=21.319(11), b=7.008(1), c=16.673(8) Å, β=133.99(2)°, V cell=1792(1) Å 3, space group C2/m, Z=2, d calc=1.879 g/cm 3 for C 20H 40N 4Nb 2S 9.72Se 2.28, Syntex P2 1, λCukα, N meas/corr=2423/1191, R(F)=0.0569 and wR(F 2)=0.1282 for 889 F hkl>4σ(F). The compound is isostructural to the thio analog Nb 2S 4(S 2CNEt 2) 4 studied earlier; in both cases, the molecule is disordered in crystals over two positions. The composition was refined by diffraction data. The results are in good agreement with the Raman and FMB (fast molecule bombardment) mass spectrometry data. The structure of Nb 2S 4(S 2CNEt 2) 4 was refined for the second time using a new model of disorder; as a result of the refinement, a normal value of S?S bond length in the S 2 ligand [2.027(5) Å] was obtained. 相似文献
12.
Conclusions The solubility of rubidium and cesium sulfates in aqueous solutions of sulfuric acid was studied at 25°. Rubidium sulfate forms the compounds 3Rb 2SO 4· H 2SO 4, Rb 2SO 4 · H 2SO 4, Rb 2SO 4·3H 2SO 4 and Rb 2SO 4·7H 2SO 4 with sulfuric acid, while cesium sulfate forms the compounds Cs 2SO 4·H 2SO 4; Cs 2SO 4·3H 2SO 4 and Cs 2SO 4 · 7H 2SO 4.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1166–1170, June, 1968. 相似文献
13.
Ten organotin derivatives with dithiocarbamates of the formulae (4‐NCC 6H 4CH 2) 2Sn(S 2CNEt 2) 2 (1), (4‐NCC 6H 4CH 2) 2Sn(S 2CNBz 2) 2 (2), (4‐NCC 6H 4CH 2) 2Sn[S 2CN(CH 2CH 2) 2NCH 3] 2 (3), (2‐ClC 6H 4CH 2) 2 Sn(S 2CNEt 2) 2 (4), (2‐ClC 6H 4CH 2) 2Sn(S 2CNBz 2) 2 (5), (4‐NCC 6H 4CH 2) 2Sn(Cl)S 2CNEt 2 (6), (4‐NCC 6H 4CH 2) 2Sn(Cl)S 2CNBz 2 (7), (4‐NCC 6H 4CH 2) 2Sn(Cl)S 2CN(CH 2CH 2) 2NCH 3 (8), (2‐ClC 6H 4CH 2) 2 Sn(Cl)S 2CNEt 2 (9) and (2‐ClC 6H 4CH 2) 2Sn(Cl)S 2CNBz 2 (10) have been prepared. All complexes were characterized by elemental analyses, IR and NMR. The crystal structures of complexes 1 and 10 were determined by X‐ray single crystal diffraction. For complex 1, the central tin atom exists in a skew‐trapezoidal planar geometry defined by two asymmetrically coordinated dithiocarbamate ligands and two 4‐cyanobenzyl groups. In addition, because of the presence of close intermolecular non‐bonded contacts, complex 1 is a weakly‐bridged dimer. In complex 10, the central tin atom is rendered pentacoordinated in a distorted trigonal bipyramidal configuration by coordinating with S atoms derived from the dithiocarbamate ligand. In vitro assays for cytotoxicity against five human tumor cell lines (MCF‐7, EVSA‐T, WiDr, IGROV and M226) furnished the significant toxicities of the title complexes. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
14.
Novel trisubstituted ethylenes, oxy ring-substituted butyl 2-cyano-3-phenyl-2-propenoates, RPhCH=C(CN)CO 2C 4H 9 (where R is 2-methoxy, 3-methoxy, 4-methoxy, 2-ethoxy, 3-ethoxy, 4-ethoxy, 4-propoxy, 4-butoxy, 4-hexyloxy, 3-phenoxy) were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of oxy ring-substituted benzaldehydes and butyl cyanoacetate and characterized by CHN elemental analysis, IR, 1H- and 13C-NMR. All the ethylenes were copolymerized with styrene (M 1) in solution with radical initiation (ABCN) at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C-NMR, GPC, DSC, and TGA. The order of relative reactivity (1/ r1) for the monomers is 4-methoxy (6.56) > 3-methoxy (2.97) > 2-methoxy (2.72) > 4-butoxy (2.20) > 3-ethoxy (2.18) > 4-propoxy (2.15) > 4-hexyloxy (1.78) > 4-ethoxy (1.66) > 2-ethoxy (1.48) > 3-phenoxy (1.29). Decomposition of the copolymers in nitrogen occurred in two steps, first in the 200-500°C range with residue (0.8–3.6% wt.), which then decomposed in the 500–800°C range. 相似文献
15.
K 2NaGaP 2, Cs 2NaGaP 2, K 2NaGaAs 2, K 2NaInP 2 and K 2NaInAs 2, Compounds with the Polyanions [MX 4/2] 3? (M?Ga, In; X?P, As) isosteric with SiS 2 The title compounds are synthesized from stoichiometric mixtures of the elements or from Na, KP(KAs), Cs 4P 6 and MX (M?Ga, In; X?P, As) at 950K. They are isotypic and crystallize in the space group Ibam (No. 72) with Z=4. The anionic partial structure is characterized by infinite chains [MX 4/2] 3? which are isosteric to SiS 2. Vibrational spectra are measured and interpreted based on the symmetry D 4h-P(2/m 2/c)4 2/m of the isolated polymer chain [MX 2] 3?. A good agreement between observed and calculated frequencies is obtained by using a force field of the tetrameric fragment [M 4X 10] 18? (three four-membered M 2X 2 rings). 相似文献
16.
The thermal behaviour of some 2-benzylamino-2-deoxyheptonic acids obtained from 2-benzylamino-2-deoxy- D- glycero- L- gluco, 2-benzylamino-2-deoxy- D- glycero- D- ido and 2-benzylamino-2-deoxy- D- glycero- D- taloheptononitriles (reported) previously has been studied in air (static atmosphere) and N 2 (dynamic atmosphere, flow rate 200 ml/min).
Zusammenfassung Das thermische Verhalten einiger aus 2-Benzylamino-2-desoxy-D-glycero-L-gluco-, 2-Benzylamino-2-desoxy-D-glycero-D-ido und 2-Benzylamino-2-desoxy-D-glycero-D-talo-heplononitril (kürzlich beschrieben) erhaltenen 2-Benzylamino-2-desoxy-heptonsäuren wurde ín Luft (statische Atmosphäre) und N2 (dynamische Atmosphäre, Strömungsgeschwindigkeit 200 ml/min) untersucht.
( 200 /) 2--2- , 2--2---uepo-L, 2-2- ---- 2-2--- -- 2--2----ma . 相似文献
17.
The new compounds K 2Au 2Ge 2S 6 ( 1 ), K 2Au 2Sn 2Se 6 ( 2 ), and Cs 2Au 2SnS 4 ( 3 ) have been synthesized through direct reaction of the elements with a molten polyalkalithiogermanate(stannate) flux at 650, 550, and 400 °C, respectively. Their crystal structures have been determined by single crystal X-ray diffraction techniques. 1 crystallizes in the monoclinic space group P2 1/n with a = 10.633(2) Å, b = 11.127(2) Å, c = 11.303(2) Å, β = 115,37(3)°, V = 1208,2(3) Å 3 and Z = 4, final R(Rw) = 0.045(0.106). 2 crystallizes in the tetragonal space group P4/mcc with a = 8.251(1) Å, c = 19.961(4) Å, V = 1358,9(4) Å 3 and Z = 4, final R(Rw) = 0.040(0.076). 3 crystallizes in the orthorhombic space group Fddd with a = 6.143(1) Å, b = 14.296(3) Å, c = 24.578(5) Å, V = 2158.4(7) Å 3 and Z = 4, final R(Rw) = 0.039(0.095). The structures of 1 , 2 , and 3 consist of infinite, one-dimensional anionic chains containing X 2Q 64– units linked by Au + ions and charge balancing K +/Cs + ions situated between the chains. All compounds were investigated with differential thermal analysis, FT-IR, and solid state UV/VIS diffuse reflectance spectroscopy. 相似文献
18.
The synthesis of three 2D interdigitated Zn II coordination polymers (CPs), by using three monotopic ligands containing C?C bonds, is reported. Among these, two CPs with 4spy (4‐styryl pyridine) and 2F‐4spy (a 2′‐fluoro derivative of 4spy) ligands showed quantitative formation of cyclobutane rings, thus demonstrating a unique synthetic procedure to synthesize metal–organic frameworks (MOFs) by using this photochemical reaction. Interestingly, these compounds can also be synthesized by mechanochemical grinding procedures by using Zn(OAc) 2. In contrast, Zn(NO 3) 2 did not yield the required product, unlike in the solution route. In addition, compounds with 4vpy (4‐vinylpyridine), 4spy and 2F‐4spy ligands created different units in the CPs; 4vpy and 2F‐4spy furnished paddle wheel units, whereas 4spy yielded tetrahedral Zn II repeating units. Furthermore, the change in coordination geometry manifests in the photoluminescence properties, attributed to the difference in charge‐transfer and ligand‐centered fluorescent phenomenon. 相似文献
19.
Bis(disulfido)bridged Nb IV cluster oxalate complexes [Nb 2(S 2) 2(C 2O 4) 4] 4– were prepared by ligand substitution reaction from the aqua ion [Nb 2(μ‐S 2) 2(H 2O) 8] 4+ and isolated as K 4[Nb 2(S 2) 2(C 2O 4) 4] · 6 H 2O ( 1 ), (NH 4) 6[Nb 2(S 2) 2(C 2O 4) 4](C 2O 4) ( 2 ) and Cs 4[Nb 2(S 2) 2(C 2O 4) 4] · 4 H 2O ( 3 ). The crystal structures of 1 and 2 were determined. The crystals of 1 belong to the space group P1, a = 720.94(7) pm, b = 983.64(10) pm, c = 1071.45(10) pm, α = 109.812(1)°, β = 91.586(2)°, γ = 105.257(2)°. The crystals of 2 are monoclinic, space group C2/c, a = 1567.9(2) pm, b = 1906.6(3) pm, c = 3000.9(4) pm, β = 95.502(2)°. The packing in 2 shows alternating layers of cluster anions and of ammonium/uncoordinated oxalates perpendicular to the [1 0 1] direction. Vibration spectra, electrochemistry and thermogravimetric properties of the complexes are also discussed. 相似文献
20.
The condensation of ethyl cyclopentanone-2-carboxylate with N-arylmethylene-2-naphthylamines depending on the conditions of reaction affords 4-aryl-l-ethoxycarbonyl-l H-2,3,4,5-tetrahydrocyclopenta-[c]benzo[f]quinolines, 4-aryl-l-ethoxycarbonyl-l H-2,3-dihydrocyclopenta[c]benzo[f]quinolines, and 4-aryll H-2,3-dihydrocyclopenta[c]benzo[f]quinolines. 相似文献
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