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1.
A novel three‐dimensional ZnII complex, poly[aqua(μ4‐5‐carboxylato‐1‐carboxylatomethyl‐2‐oxidopyridinium)zinc(II)], [Zn(C8H5NO4)(H2O)]n, has been prepared by hydrothermal assembly of Zn(CH3COO)2·2H2O and 5‐carboxy‐1‐(carboxymethyl)pyridin‐1‐ium‐2‐olate (H2ccop). The ccop2− anions bridge the ZnII cations in a head‐to‐tail fashion via monodentate aromatic carboxylate and phenolate O atoms to form an extended zigzag chain which runs parallel to the [011] direction. One O atom of the aliphatic carboxylate group of the ccop2− ligand coordinates to the ZnII atom of a neighbouring chain thereby producing undulating layers which lie parallel to the (01) plane. A similar parallel undulating planar structure can be obtained if a path involving the other O atom of the aliphatic carboxylate group is considered. Thus, the aliphatic carboxylate group acts in a bridging bidentate mode to give extended –Zn–O–C–O–Zn– sequences running parallel to [001] which link the layers into an overall three‐dimensional framework. The three‐dimensional framework can be simplified as a 4‐connected sra topology with a Schläfli symbol of 42.63.8 if all the ZnII centres and ccop2− anions are regarded as tetrahedral 4‐connected nodes. The three‐dimensional luminescence spectrum was measured at room temperature with excitation and emission wavelengths of 344–354 and 360–630 nm, respectively, at intervals of 0.15 and 2 nm, respectively.  相似文献   

2.
薛思佳  卞王东  柴安  吁松瑞 《中国化学》2008,26(8):1501-1505
本文首次合成标题化合物N-(4-甲基苯甲酰氨基)-N’-[5-(2-三氟甲基苯基)-2-呋喃甲酰硫脲。化合物(C21H16F3N3O3S, Mr = 447.43)单晶经测定为单斜晶体,空间群为P -1。在晶体中,存在一些分子内和分子间的相互作用,分子间还有C—H···π 的相互作用,这可能导致晶体更稳定的原因。目标产物的结构经IR, H NMR和元素分析测定确证。初步生物活性测试表明,部分化合物对棉花枯萎病、黄瓜灰霉病、苹果轮纹病和棉花炭疽病有较好的选择性杀菌活性;部分目标化合物有较好的除草活性。  相似文献   

3.
The reactions of 5‐benzylidene‐3‐phenylrhodanine ( 2 ; rhodanine=2‐thioxo‐1,3‐thiazolidin‐4‐one) with diazomethane ( 7a ) and phenyldiazomethane ( 7b ) occurred chemoselectively at the exocyclic C?C bond to give the spirocyclopropane derivatives 9 and, in the case of 7a , also the C‐methylated products 8 (Scheme 1). In contrast, diphenyldiazomethane ( 7c ) reacted exclusively with the C?S group leading to the 2‐(diphenylmethylidene)‐1,3‐thiazolidine 11 via [2+3] cycloaddition and a ‘two‐fold extrusion reaction’. Treatment of 8 or 9b with an excess of 7a in refluxing CH2Cl2 and in THF at room temperature in the presence of [Rh2(OAc)4], respectively, led to the 1,3‐thiazolidine‐2,4‐diones 15 and 20 , respectively, i.e., the products of the hydrolysis of the intermediate thiocarbonyl ylide. On the other hand, the reactions with 7b and 7c in boiling toluene yielded the corresponding 2‐methylidene derivatives 16, 21a , and 21b . Finally, the reaction of 11 with 7a occurred exclusively at the electron‐poor C?C bond, which is conjugated with the C?O group. In addition to the spirocyclopropane 23 , the C‐methylated 22 was formed as a minor product. The structures of the products (Z)‐ 8, 9a, 9b, 11 , and 23 were established by X‐ray crystallography.  相似文献   

4.
The reaction of 4‐amino‐1,2,4‐Δ2‐triazoline‐5‐thione (ATT, 1 ) with AgNO3 in methanol led to the complex [Ag(ATT)2]NO3 ( 2 ). 2 was characterized by elemental analyses, 1H NMR, IR, and Raman spectroscopy as well as single‐crystal X‐ray diffraction. The molecular structure of 1 was also determined by single crystal X‐ray analysis. Crystal data for 1 at ?80 C: space group C2/c with a = 2107.4(2), b = 1425.1(1), c = 688.4(1) pm, β = 104.55(1)°, Z = 16, R1 = 0.0514, crystal data for 2 at ?80 °C: space group P21/c with a = 675.7(1), b = 1321.1(1), c = 1311.2(1) pm, β = 90.03(1)°, Z = 4, R1 = 0.0437.  相似文献   

5.
The polymorphic study of 3‐(3‐phenyl‐1H‐1,2,4‐triazol‐5‐yl)‐2H‐1‐benzopyran‐2‐one, C17H11N3O2, was performed due to its potential biological activity and revealed three polymorphic modifications in the triclinic space group P, the monoclinic space group P21 and the orthorhombic space group Pbca. These polymorphs have a one‐column layered type of crystal organization. The strongest interactions between the molecules of the studied structures is stacking between π‐systems, while N—H…N and C—H…O hydrogen bonds link stacked columns forming layers as a secondary basic structural motif. C—H…π hydrogen bonds were observed between neighbouring layers and their role is the least significant in the formation of the crystal structure. Packing differences between the polymorphic modifications are minor and can be identified only using an analysis based on a comparison of the pairwise interaction energies.  相似文献   

6.
Reaction of [Au(DAPTA)(Cl)] with RaaiR’ in CH2Cl2 medium following ligand addition leads to [Au(DAPTA)(RaaiR’)](Cl) [DAPTA=diacetyl-1,3,5-triaza-7-phosphaadamantane, RaaiR’=p-R-C6H4-N=N- C3H2-NN-1-R’, (1—3), abbreviated as N,N’-chelator, where N(imidazole) and N(azo) represent N and N’, respectively; R=H (a), Me (b), Cl (c) and R’=Me (1), CH2CH3 (2), CH2Ph (3)]. The 1H NMR spectral measurements in D2O suggest methylene, CH2, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph it shows AB type quartets. 13C NMR spectrum in D2O suggest the molecular skeleton. The 1H-1H COSY spectrum in D2O as well as contour peaks in the 1H-13C HMQC spectrum in D2O assign the solution structure.  相似文献   

7.
The title compounds, 3,5,7‐triphenyl‐1,2‐diazacyclohepta‐1(7),2‐diene, C23H20N2, (I), and 3,7‐bis(2‐hydroxyphenyl)‐5‐phenyl‐1,2‐diazacyclohepta‐1(7),2‐diene, C23H20N2O2, (II), constitute the first structurally characterized examples of seven‐membered heterocycles with 1,2‐diaza ring N atoms. Compound (I) crystallizes in the space group P, with two independent molecules in the asymmetric unit that differ in the conformation of one of the phenyl rings, while (II) crystallizes in the space group C2/c. The C5N2 ring in each of (I) and (II) adopts a twist‐boat conformation. Compound (I) exhibits neither C—H...π interactions nor π–π stacking interactions, whereas (II) shows both intramolecular O—H...N hydrogen bonds and a C—H...π interaction that joins the molecules into an infinite chain in the [010] direction.  相似文献   

8.
Four crystal structures of 3‐cyano‐6‐hydroxy‐4‐methyl‐2‐pyridone (CMP), viz. the dimethyl sulfoxide monosolvate, C7H6N2O2·C2H6OS, (1), the N,N‐dimethylacetamide monosolvate, C7H6N2O2·C4H9NO, (2), a cocrystal with 2‐amino‐4‐dimethylamino‐6‐methylpyrimidine (as the salt 2‐amino‐4‐dimethylamino‐6‐methylpyrimidin‐1‐ium 5‐cyano‐4‐methyl‐6‐oxo‐1,6‐dihydropyridin‐2‐olate), C7H13N4+·C7H5N2O2, (3), and a cocrystal with N,N‐dimethylacetamide and 4,6‐diamino‐2‐dimethylamino‐1,3,5‐triazine [as the solvated salt 2,6‐diamino‐4‐dimethylamino‐1,3,5‐triazin‐1‐ium 5‐cyano‐4‐methyl‐6‐oxo‐1,6‐dihydropyridin‐2‐olate–N,N‐dimethylacetamide (1/1)], C5H11N6+·C7H5N2O2·C4H9NO, (4), are reported. Solvates (1) and (2) both contain the hydroxy group in a para position with respect to the cyano group of CMP, acting as a hydrogen‐bond donor and leading to rather similar packing motifs. In cocrystals (3) and (4), hydrolysis of the solvent molecules occurs and an in situ nucleophilic aromatic substitution of a Cl atom with a dimethylamino group has taken place. Within all four structures, an R22(8) N—H...O hydrogen‐bonding pattern is observed, connecting the CMP molecules, but the pattern differs depending on which O atom participates in the motif, either the ortho or para O atom with respect to the cyano group. Solvents and coformers are attached to these arrangements via single‐point O—H...O interactions in (1) and (2) or by additional R44(16) hydrogen‐bonding patterns in (3) and (4). Since the in situ nucleophilic aromatic substitution of the coformers occurs, the possible Watson–Crick C–G base‐pair‐like arrangement is inhibited, yet the cyano group of the CMP molecules participates in hydrogen bonds with their coformers, influencing the crystal packing to form chains.  相似文献   

9.
The title compound, [Ag2(C6H4N4)(N3)]n, was obtained under hydrothermal conditions at 433 K. The asymmetric unit of the orthorhombic space group (Pna21) consists of two Ag+ cations, an anionic 5‐(pyridin‐4‐yl)tetrazolide (4‐ptz) ligand and an anionic azide ligand. Both Ag+ centres are coordinated by four N atoms, forming a distorted tetrahedral coordination environment. When all the component ions are viewed as 4‐connected nodes, the whole three‐dimensional network can be regarded topologically as a new kind of 4,4,4,4‐connected net with the Schläfli symbol (4.85)(42.84)(43.83)2.  相似文献   

10.
NMR spectra of the synthesized azo dyes, 5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones (5a–g), 1,3‐dimethyl‐5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones (6a–g), and 5‐arylazo‐2‐thioxo‐pyrimidine (1H,3H,5H)‐4,6‐diones (7a–g) were studied in (CD3)2SO (three drops of CD3OD were added into solutions of the dyes in two different concentrations). All dyes showed intramolecular hydrogen bonding. Dyes 5a–7a showed bifurcated intramolecular hydrogen bonds. Tautomeric behaviours of some of N‐methylated azo dyes (6a‐g) were studied in two different concentrations. The solvent–substrate proton exchange of dyes 5a–d, 6a and 7a–e was examined in presence of three drops of CD3OD. The dyes which were soluble in (CD3)2SO containing CD3OD showed isotopic splitting (β‐isotope effect) in the 13C NMR spectra. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

11.
3‐Nitro‐1,2,4‐triazol‐5‐one (NTO) europium complex of [Eu(NTO)3(H2O)5]·5H2O was synthesized by mixing the aqueous solution of lithium 3‐nitro‐1,2,4‐triazol‐5‐onate and the dilute nitric acid solution of europium oxide. The title complex was characterized by elemental analysis and IR spectra. The single crystal structure was determined by a four‐circle x‐ray diffractometer. The title complex is monoclinic with space group P21/n and unit cell parameters of a = 1.8720(2) nm, b = 0.6548(3) nm, c = 1.9323(3) nm and β = 95.33(1)°. The coordination geometry around the europium ion is a distorted dodecahedron and there are five crystalline water molecules to form the stable structure of the crystal. From measurements of the enthalpy of solution in water at 298.15 K, the standard enthalpy of formation, lattice enthalpy and lattice energy have been determined as ‐(3798.6 ± 3.7), ?4488.4 and ?4452.4 kJ·mol?;1, respectively.  相似文献   

12.
The synthesis of α‐benzamido‐α‐benzyl lactones 23 of various ring size was achieved either via ‘direct amide cyclization’ by treatment of 2‐benzamido‐2‐benzyl‐ω‐hydroxy‐N,N‐dimethylalkanamides 21 in toluene at 90 – 110° with HCl gas or by ‘ring transformation’ of 4‐benzyl‐4‐(ω‐hydroxyalkyl)‐2‐phenyl‐1,3‐oxazol‐5(4H)‐ones under the same conditions. The precursors were obtained by C‐alkylations of 4‐benzyl‐2‐phenyl‐1,3‐oxazol‐5(4H)‐one ( 15 ) with THP‐ or TBDMS‐protected ω‐hydroxyalkyl iodides. Ring opening of the THP‐protected oxazolones by treatment with Me2NH followed by deprotection of the OH group gave the diamides 21 , whereas deprotection of the TBDMS series of oxazolones 25 with TBAF followed by treatment with HCl gas led to the corresponding lactones 23 in a one‐pot reaction.  相似文献   

13.
The ten‐coordinate complex, (HATr)[Na(DNMz)] · H2O ( 1 ) was synthesized by reaction of 5‐(dinitromethylene)‐4,5‐dihydro‐1H‐tetrazole (DNMz), sodium hydroxide, and 3‐hydrazinium‐4‐amino‐1,2,4‐1H‐triazolium dichloride (HATr) in aqueous solution and characterized by various physico‐chemical techniques. Complex 1 is an energetic material with a nitrogen content of 51.2 % and a decomposition temperature of 128.9 °C. The molecular structure of complex 1 crystallizes in the monoclinic system with P2(1)/c group and shows an infinite 1D chain structure. The heat of formation was determined as –122.27 kJ · mol–1 by using bomb calorimetry. In addition, the kinetic parameters were studied by Kissinger's and Ozawa‐Doyle's methods.  相似文献   

14.
The reaction of 1H‐imidazole‐4‐carbohydrazides 1 , which are conveniently accessible by treatment of the corresponding esters with NH2NH2?H2O, with isothiocyanates in refluxing EtOH led to thiosemicarbazides (=hydrazinecarbothioamides) 4 in high yields (Scheme 2). Whereas 4 in boiling aqueous NaOH yielded 2,4‐dihydro‐3H‐1,2,4‐triazole‐3‐thiones 5 , the reaction in concentrated H2SO4 at room temperature gave 1,3,4‐thiadiazol‐2‐amines 6 . Similarly, the reaction of 1 with butyl isocyanate led to semicarbazides 7 , which, under basic conditions, undergo cyclization to give 2,4‐dihydro‐3H‐1,2,4‐triazol‐3‐ones 8 (Scheme 3). Treatment of 1 with Ac2O yielded the diacylhydrazine derivatives 9 exclusively, and the alternative isomerization of 1 to imidazol‐2‐ones was not observed (Scheme 4). It is important to note that, in all these transformations, the imidazole N‐oxide residue is retained. Furthermore, it was shown that imidazole N‐oxides bearing a 1,2,4‐triazole‐3‐thione or 1,3,4‐thiadiazol‐2‐amine moiety undergo the S‐transfer reaction to give bis‐heterocyclic 1H‐imidazole‐2‐thiones 11 by treatment with 2,2,4,4‐tetramethylcyclobutane‐1,3‐dithione (Scheme 5).  相似文献   

15.
The title compound {systematic name: 4‐amino‐5‐cyclopropyl‐7‐(2‐deoxy‐β‐D‐erythro‐pentofuranosyl)‐7H‐pyrrolo[2,3‐d]pyrimidine}, C14H18N4O3, exhibits an anti glycosylic bond conformation, with the torsion angle χ = −108.7 (2)°. The furanose group shows a twisted C1′‐exo sugar pucker (S‐type), with P = 120.0 (2)° and τm = 40.4 (1)°. The orientation of the exocyclic C4′—C5′ bond is ‐ap (trans), with the torsion angle γ = −167.1 (2)°. The cyclopropyl substituent points away from the nucleobase (anti orientation). Within the three‐dimensional extended crystal structure, the individual molecules are stacked and arranged into layers, which are highly ordered and stabilized by hydrogen bonding. The O atom of the exocyclic 5′‐hydroxy group of the sugar residue acts as an acceptor, forming a bifurcated hydrogen bond to the amino groups of two different neighbouring molecules. By this means, four neighbouring molecules form a rhomboidal arrangement of two bifurcated hydrogen bonds involving two amino groups and two O5′ atoms of the sugar residues.  相似文献   

16.
The 2‐hydroxy‐3,5,5‐trimethylcyclopent‐2‐en‐1‐one ( 1 ) was synthesized in 42% yield by rearrangement of epoxy ketone 10 on treatment with BF3⋅Et2O under anhydrous conditions. Intermediate 10 was available from the known enone 8 , either via direct epoxidation (60% H2O2, NaOH, MeOH; yield 50%), or via reduction to the corresponding allylic alcohol 14 (LiAlH4, THF), followed by epoxidation ([VO(acac)2], tBuOOH) and reoxidation under Swern conditions, in 37% total yield.  相似文献   

17.
Biginelli compounds 1 were first brominated at Me? C(6) with 2,4,4,6‐tetrabromocyclohex‐2,5‐dien‐1‐one to give Br2CH? C(6) derivatives 2 . The hydrolysis of the 6‐(dibromomethyl) group of 2c to give the 6‐formyl derivative 3c in the presence of an expensive Ag salt followed by reaction with N2H4?H2O yielded tetrahydropyrimido[4,5‐d]pyridazine‐2,5(1H,3H)‐dione ( 4c ; Scheme 1). However, treatment of the 6‐(dibromomethyl) derivatives 2 directly with N2H4?H2O led to the fused heterocycles 4 in better overall yield (Schemes 1 and 2; Table).  相似文献   

18.
The title coordination polymer, {[Cd2(CH2N5)(C6H4NO2)Cl(OH)]·0.14H2O}n, (I), was synthesized by the reaction of cadmium acetate and N‐(1H‐tetrazol‐5‐yl)isonicotinamide in aqueous ammonia, using hydrochloric acid to adjust the pH. Under hydrothermal conditions, N‐(1H‐tetrazol‐5‐yl)isonicotinamide slowly hydrolyzes to form isonicotinic acid (Hisonic) and 5‐aminotetrazole (Hatz). The deprotonated form of isonicotinic acid (denoted isonic) acts as a bridging ligand in the structure. The polymer crystallizes in the monoclinic space group C2/m. In the structure, there is one Cd33‐OH) unit of Cs symmetry, with one of the CdII atoms and the O and H atoms located on a mirror plane. The other crystallographically independent CdII cation is located on an inversion centre. Each edge of the Cd33‐OH) isosceles triangle is bridged by an atz ligand in a μ1,2 or μ2,33,4 mode. The Cd33‐OH) units are laced around with a belt of chloride ligands. The belts are further connected into undulating layers via weak inter‐belt Cd—Cl bonds. The two organic ligands reside across mirror planes. The construction of a three‐dimensional framework is completed by the pillaring isonic ligand. Water molecules partially occupy the voids of the framework.  相似文献   

19.
In the coordination polymer catena‐poly[[[diaqua[5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylato‐κ2N3,O4]lead(II)]‐μ‐5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylato‐κ3N3,O4:N2] dihydrate], {[Pb(C10H6N3O4)(H2O)2]·2H2O}n, the two 5‐carboxy‐2‐(pyridin‐3‐yl)‐1H‐imidazole‐4‐carboxylate ligands have different coordination modes, one being terminal and the other bridging. The bridging ligand links PbII cations into one‐dimensional coordination polymer chains. The structure is also stabilized by intra‐ and interchain π–π stacking interactions between the pyridine rings, resulting in the formation of a two‐dimensional network. Extensive hydrogen‐bonding interactions lead to the formation of a three‐dimensional supramolecular network.  相似文献   

20.
We report the efficient preparation of furo[2,3‐d]pyridazin‐4(5H)‐one and its N‐substituted derivatives starting from methyl 2‐methylfuran‐3‐carboxylate. The Me group was converted to the aldehyde group, which was then condensed with hydrazine derivatives. Then, the ester functionalities were hydrolyzed to the corresponding acids, followed by treatment with SOCl2 to give N‐substituted furopyridazinone derivatives.  相似文献   

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