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1.
The alkali dicyanamides M[N(CN)2] (M=K, Rb) were synthesized through ion exchange, and the corresponding tricyanomelaminates M3[C6N9] were obtained by heating the respective dicyanamides. The thermal behavior of the dicyanamides and their reaction to form the tricyanomelaminates were investigated by temperature-dependent X-ray powder diffractometry and thermoanalytical measurements. Potassium dicyanamide K[N(CN)2] was found to undergo four phase transitions: At 136 degrees C the low-temperature modification alpha-K[N(CN)2] transforms to beta-K[N(CN)2], and at 187degrees C the latter transforms to the high-temperature modification gamma-K[N(CN)2], which melts at 232 degrees C. Above 310 degrees C the dicyanamide ions [N(CN)2]- trimerize and the resulting tricyanomelaminate K3[C6N9] solidifies. Two modifications of rubidium dicyanamide have been identified: Even at -25 degrees C, the a form slowly transforms to beta-Rb[N(CN)2] within weeks. Rb[N(CN)2] has a melting point of 190 degrees C. Above 260 degrees C the dicyanamide ions [N(CN)2]- of the rubidium salt trimerize in the melt and the tricyanomelaminate Rb3[C6N9] solidifies. The crystal structures of all phases were determined by powder diffraction methods and were refined by the Rietveld method. alpha-K[N(CN)2] (Pbcm, a = 836.52(1), b = 46.90(1), c =7 21.27(1) pm, Z = 4), gamma-K[N(CN)2] (Pnma, a = 855.40(3), b = 387.80(1), 1252.73(4) pm, Z = 4), and Rb[N(CN)2] (C2/c, a = 1381.56(2), b = 1000.02(1), c = 1443.28(2) pm, 116.8963(6) degrees, Z = 16) represent new structure types. The crystal structure of beta-K[N(CN)2] (P2(1/n), a = -726.92(1), b 1596.34(2), c = 387.037(5) pm, 111.8782(6) degrees, Z = 4) is similar but not isotypic to the structure of alpha Na[N(CN)2]. alpha-Rb[N(CN)2] (Pbcm, a = 856.09(1), b = 661.711(7), c = 765.067(9) pm, Z = 4) is isotypic with alpha-K[N(CN)2]. The alkali dicyanamides contain the bent planar anion [N(CN)2]- of approximate symmetry C2, (average bond lengths: C-N(bridge) 133, C-N(term) 113 pm; average angles N-C-N 170 degrees, C-N-C 120 degrees). K3[C6N9] (P2(1/c), a = 373.82(1), b = 1192.48(5), c = 2500.4(1) pm, beta = 101.406(3) degrees, Z = 4) and Rb,[C6N9] (P2(1/c), a = 389.93(2), b = 1226.06(6), c = 2547.5(1) pm, 98.741(5) degrees, Z=4) are isotypic and they contain the planar cyclic anion [C6N9]3-. Although structurally related, Na3[C6N9] is not isotypic with the tricyanomelaminates M3[C6N9] (M = K, Rb).  相似文献   

2.
Ba[CoN]: A Low-Valency Nitridocobaltate with Angled Chains [CoN2/22?] Ba[CoN] is prepared by reaction of barium and cobalt (molar ratio Ba : Co = 1 : 2.5) in tantalum crucibles at 870°C with flowing nitrogen (1 atm) within a period of 96 h. After cooling down to room temperature (24°C/h) black single crystals of the ternary phase with a platy habit are obtained (orthorhombic, Pnma; a = 959.9(2) pm, b = 2 351.0(3) pm, c = 547.6(2) pm; Z = 20). The crystal structure of Ba[CoN] contains angled (planar) chains [CoN2/22?] which run along the [010]-direction (N? Co? N[°]: 178.5(5), 179.6(6), 180.0; Co? N? Co[°]: 82.9(6), 84.2(5), 177.1(8); Co? N[pm]: 174.6(12), 177.2(12), 181.9(13), 184.3(13), 187.1(12)). Nitrogen is in an octahedral coordination (N Ba4Co2) and is arranged in a distorted cubic close packing. Barium occupies one half of the tetrahedral holes (Ba? N[pm]: 274.8(16) ? 308.2(12)). The cis-positions of the Co-atoms at the nitrogen coordination-octahedra cause short Co? Co contacts within the chains [CoN2/22?]. Through this, Co2-units (Co? Co[pm]: 247.8(4); bridged by nitrogen) and linear Co3-groups (Co? Co [pm]: 245.5(2); Co? Co? Co[°]: 180.0; bridged by nitrogen) alternate along the chains. The crystal structure of Ba[CoN] is closely related to the Ba[NiN] type structure.  相似文献   

3.
8,9,12-Trihydro-9,9-pentamethylene-12-(3-nitrophenyl)-11H-naphtho[1',25,6]-pyrano[2,3-d]pyrimidin-11(10H)-one 1,another conversion product of Friedlndler reaction,has been synthesized by the reaction of 2-amino-4-(3-nitrophenyl)-4H-benzo[f]chromene-3-carbo-nitrile 2 with cyclohexanone in the presence of Lewis acid catalysts.The crystal of the title compound 1 THF solvate,C60H62N6O10,was obtained and determined by X-ray diffraction me-thod.The crystal is of triclinic,space group P with a = 11.4633(11),b = 12.6247(12),c = 19.658(2) ,α = 72.642(8),β = 89.045(9),γ = 68.340(5)°,V = 2509.6(4),Z = 2,Dc = 1.359 g/cm3,F(000) = 1088,Mr = 1027.16,the final R = 0.0674 and wR = 0.1869 with Ⅰ > 2σ(Ⅰ) and the goodness-of-fit S = 1.045 on F2.The pyrimidine ring has an envelope conformation,linked with a six-membered ring through a spiro C atom.The crystal packing of 1 THF solvate is stabilized by N-H···O hydrogen bonds,and π-π stacking interaction occurs between two adjacent nearly planar molecules of 1.  相似文献   

4.
Colorless single crystals of Cd[AlCl4]2 grow from the melt of CdCl2 and AlCl3 upon slow cooling from 250°C. The crystal structure [monoclinic, P1a1, Z = 2, a = 1288.7(2), b = 660.2(1), c = 705.1(1) pm, β = 92.89(1)º] may be derived from hexagonally closest packed layers of Cl?. Octahedral and tetrahedral holes are filled with Cd2+ and Al3+ in a 1:2 ratio between all layers stacked in the [104] direction. Cd[GaCl4]2 and Cd[AlBr4]2 are isotypic. Reduction of Cd[AlCl4]2 with excess cadmium shot and slow cooling from 350°C yields plate-like very moisture-sensitive, colorless single crystals of Cd2[AlCl4]2. The crystal structure [triclinic, C1 , Z = 2, a = 655.47(3), b = 1135.26(1), c = 935.23(6) pm, α = 89.70(2)º, β = 103.61(1)º, γ = 90.455(1)º] is built from slabs stacked in the [100] direction consisting of ethane-like [Cd2Cl6] units with a Cd? Cd distance of 256.1 pm sharing common vertices with [AlCl4] tetrahedra.  相似文献   

5.
The nmr and X-ray diffraction data of the novel ring system furo[3,2-e]imidazo[1,2-c]pyrimidine are reported in this paper. The crystal and molecular structure of this compound (C9H7N3O2·1/2H2O) has been solved at room temperature. Crystals are monoclinic in a space group of P2/n with cell constants a = 9.982(8), b = 13.526(9) and c = 13.981(9) Å, β = 107.44(5)°, V = 1800.9 Å3, Z = 8, Dx = 1.462 Mg·m?3. The structure was solved by full matrix least square refinement giving a final R = 0.054 (Rw = 0.069) for 1263 reflections (I>3.0σ(I)). The compound is essentially planar, existing in two slightly structural different forms, A and B. These are held in pairs with symmetry related molecules by hydrogen bonds formed with two water molecules. Then the dimeric units are stacked parallel to the c axis to form the tridimensional packing.  相似文献   

6.
The structure of the compound, 1-azabicyclo[3.2.0]heptane-1-methyl chloride has been determined by a single crystal x-ray diffraction study. The compound crystallizes in space group Cmcm with four formula weights in a unit cell of dimensions a = 8.53, b = 10.30, c = 9.27 ± .01 Å. The molecular cations fit in large holes between the chloride anions and consequently are disordered about the cation positions. The five-membered ring portion is non-planar and bears a strong resemplance to other five-membered rings in bicyclic-fused compounds. The azetidine portion of the molecule is planar. The basic fused ring structure is contrasted to that found in penicillin salts. A final value of R = 0.106 for the 305 independent reflections was obtained.  相似文献   

7.
<正> The title compound was synthesized and its structure solved. The formula is [Et4N]3[Fe3(SPh)3Br3Cl3]. M=1231.95, monoclinic, space group C2/c, a=24.569(4), b=13.504(2), c=18.348.(3)A, β=110.78(1)°, V=5691(3)A3, Z=4, Dm= 1.41, Dc=1.44-g/cm3. The flat structure of the anion has. a planar [Fe3S3] ring and three phenyl groups. Statistical distribution of chlorine and bromine atoms on two sides of the [Fe3S3] plane results in a C2 symmetry of the anion.  相似文献   

8.
1INTRoDUCTIONMacrocycliccoordinationcomPOundshavebeenwidelyinvestigatedinthepastdecadesbecauseoftheirrelationshiptocomplexesofbiologicalsignificancesuchasthePorphyrinsandcorrins(lJ.Structuresofmanymacrocycliccompoundshavebeenre-ported,especiallythecompoundscontainingN4macrocyclicligands"'.However,toourknowledge,onlyafewcrystalstructuresofcomplexbimetallicsaltscontainingmacrocyclicligandshavebeendeterminedbyX-raydiffractionmethod.Inthispa-per,werePortthesynthesisandstructureofthetit1ecom…  相似文献   

9.
Di-n-butyltin(IV) and diethyltin(IV) 2,3,4-, 2,4,5- and 3,4,5-trimethoxybenzoates [(CH3O)3C6H2COO]2SnR [Type a] and {[(CH3O)3C6H2COO]R2Sn}2O [Type b] have been synthesized and characterized spectroscopically. The crystal structure of bis[di-n-butyl(3,4,5- trimethoxybenzoato)tin] oxide has been determined. The triclinic unit cell contains one centrosymmetric dimer; a = 15.919(2) Å, b = 11.711(3) Å, c = 13.475(1) Å, and α = 63.63(2)°, β = 67.49(1)°, γ = 76.61(2)°. The geometry of the dimer is very similar to that of bis[di-n-butyl(5-methoxysalicylatotin] oxide), with two different types of five-coordinate tin atoms and one central planar Sn2O2 ring.  相似文献   

10.
Cycloaddition Reactions of Isocyanides with Bis[tris(trimethylsilyl)methyl]diphosphene The [2 + 1] cycloaddition reactions of isocyanoacetonitrile ( 1 a ), pentacarbonyl(diisocyanomethane)chromium ( 1 b ), and 2,2,2-trifluoroethylisocyanide ( 1 c ) with the diphosphene R–P=P–R (R = C[Si(CH3)3]) ( 2 ) yield the expected diphosphirane imines 3 a – c . All compounds are thermally very stable and show no evidence for a [2 + 1] cycloreversion reaction. The structures of 3 a : triclinic, P 1, a = 918.0(2), b = 1174.7(4), c = 1821.9(5) pm, α = 93.83(2), β = 97.22(2)°, γ = 97.08(2)°, Z = 2, R1 = 0.069; 3 c : monoclinic, P21, a = 928.6(2), b = 1659.8(3), c = 1261.2(3) pm, β = 107.65(2)°, Z = 2, R1 = 0.073, and 1,2-Bis[tris(trimethylsilyl)]methyl-N-trifluormethyl-3-diphosphiranimin: monoclinic, P21/n, a = 1374.6(3), b = 1685.9(1), c = 1658.6(5) pm, β = 108.99(9)°, Z = 4, R1 = 0.092, were elucidated by X-ray crystallography. All three compounds possess a similar three membered PCP ring system with an exocyclic C–N double bond.  相似文献   

11.
Crystal Structures of [Et3PNAsPh3]2[Ag2Br4] and [Et3PNAsPh3]2[Pd2Br6] Colourless single crystals of [Et3PNAsPh3]2[Ag2Br4]( 1 ) and red single crystals of [Et3PNAsPh3]2[Pd2Br6]( 2 ) have been isolated from saturated solutions in acetonitrile of equivalent mixtures of [Et3PNAsPh3]Br with AgBr and PdBr2, respectively. Both complexes were characterized by IR spectroscopy and by crystal structure determinations. 1 : Space group P1¯, Z = 1, lattice dimensions at ‐70°C: a = 985.0(2), b = 1042.2(5), c = 1345.8(5) pm, α = 102.88(2)°, β = 105.73(2)°, γ = 94.94(2)°, R1 = 0.0577. 2 : Space group P21/c, Z = 2, lattice dimension at ‐70°C: a = 1003.0(1), b = 1371.8(2), c = 1974.0(1) pm, β = 93.30(1)°, R1 = 0.0458. The dimeric anions of 1 and 2 form planar, centrosymmetric complex units.  相似文献   

12.
The title compound 8-(2,3-dimethoxyphenyl)-10,11,12,13-tetrahydro-9H-benzo[f]-cyclohepta[c]quinoline(C26H25NO2,Mr=383.47) was synthesized and characterized by IR,1H NMR,13C NMR and elemental analysis.The crystal belongs to triclinic,space group P1 with a= 8.1490(16),b=9.2550(19),c=14.373(3) ,α=86.96(3),β=89.66(3),γ=70.32(3)°,Z=2,V=1019.2(4) 3,Dc=1.250 g·cm-3,μ(MoKα)=0.078 mm-1,F(000)=408,the final R=0.0555 and wR=0.1240 for 2228 observed reflections(Ⅰ > 2σ(Ⅰ)).X-ray analysis reveals that the seven-numbered ring is slightly similar to a six-numbered ring,forming the chair-like conformation.The four rings(Ⅰ,Ⅱ,Ⅲ and Ⅳ) in the benzo[f]cyclohepta[c]quinoline moiety form a screw structure.  相似文献   

13.
<正> The title compound was synthesized by Friedel-Crafts reaction of tetrahydroxycalix [4] arene and propionyl choride, and its crystal structure was determined by X-ray diffraction technique. C10O8H40,Mr = 648. 75, triclinic, space group P1 with cell parameters, a = 9. 930(5), b = 11. 838(3), c=14. 522(7) A,α= 94. 92(3),β=102. 96(4),γ= 98. 32(3)°, V = 1635A3, Z = 2, Dc = 1. 399g/ cm3, μ(CuKa) = 3. 27cm-1, F (000) = 344. The final R = 0. 075, Rw = 0.092 for 5716 independent reflections with I>3σ(I). The crystal structure analysis shows that the molecule exists in fine cone conformation.  相似文献   

14.
The crystal and molecular structure of 9-(p-iodophenyl)-9-azatetracyclo[5.3.1.02,6 .08,10]-undec-4-ene (C16H16IN) has been determined by single crystal x-ray diffraction methods. The compound crystallizes in space group P21, (no. 4) with unit cell constants: a = 11.269 (1), b = 7.607 (1), c = 16.714 (1) Å, β = 104.73 (1)°. The structure was solved by the heavy-atom method and refined by block-diagonal least-squares to a final R-value of 0.054 for the 1546 independently measured, statistically significant reflections. The aziridine ring is fused to the norbornyl rather than to the five-membered ring as previously assumed. The nitrogen to phenyl-carbon distance is 1.406 Å and indicates a significant amount of double bond character.  相似文献   

15.
The synthesis of some new pyrazolo[3′,4′:6,7]azepino[5,4,3‐cd] indoles (10a‐c) was achieved via regios‐elective cyclization of the respective 3‐(4‐acylaminopyrazol‐5‐yl)indoles (9a‐c) under Bischler‐Napieralski reaction conditions. The latter compounds were obtained by acylation of the corresponding 3‐(4‐aminopyra‐zol‐5‐yl)indoles (8a,b) which, in turn, were prepared by reduction of the 3‐(4‐nitropyrazol‐5‐yl)indoles precursors (7a,b) . The latter synthons were accessible from the reaction of indolylzinc chlorides (5a,b) with 5‐chloro‐1,3‐dimethyl‐4‐nitropyrazole. Ms and nmr spectral data of 10a‐c are in agreement with the assigned azepino‐indole structure as determined for 10a by X‐ray crystal measurements which demonstrate that the azepine ring is almost completely planar with the indole and pyrazole rings.  相似文献   

16.
1 INTRODUCTIONInrecentyears ,triazolo[3,4, b] 1 ,3,4 thiadiazolederivativeshavebeenat tractingmuchattentionfromchemistsandpharmacologistsbecausetheyshowbroadspectraofbiologicalactivities,suchasinsecticidal[1 ] ,antifungal[2 ] ,herbicidal[3] ,an tibacterial[4] ,hypotensiv…  相似文献   

17.
The compound 10-phenylpyrido[3,2-b][1,4]benzothiazine 5-oxide, 1 , has been obtained in nearly quantitative yield oxidation of 10-phenylpyrido[3,2-b][1,4]benzothiazine with oxygen in dioxane solution. The 13C nmr chemical shift assignments of 1 are reported. Its structure has been determined by X-ray single crystal methods. The crystals of 1 are monoclinic, space group P21/n. There are four molecules in a unit-cell of dimensions a = 12.347(3), b = 12.947(3), c = 8.987(1)Å, β = 106.73(1)° and V = 1375.8(5) Å3. The central ring is in a boat conformation and the sulfoxide oxygen atom occupies the axial position. The folding angle between the planes of the pyrido and the benzo planes is 161.55(9)°.  相似文献   

18.
The title compound 2-oxo-3-phenyl-1-oxaspiro[4.5]dec-3-en-4-yl 4-chloro-benzoate 6 (C22H19ClO4, Mr = 382.82) has been synthesized by the condensation reaction of 4-hydroxy-3-phenyl-1-oxaspiro[4.5]dec-3-en-2-one 5 with 4-chlorobenzoyl chloride, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/n with a = 10.6749(11), b = 6.0573(7), c = 29.680(2) , β = 94.073(3)o, V = 1914.3(3) 3, Z = 4, Dc = 1.328 g/cm3, F(000) = 800, μ = 0.224 mm–1, S = 1.003, the final R = 0.0605 and wR = 0.1500 for 1828 observed reflections with I > 2σ(I) and 244 variable parameters. The crystal analysis shows that the molecular structure of the title compound has one planar furan ring, one chair conformation cyclohexane ring and two benzene rings. The furan and cyclohexane rings adopt whorl conformations.  相似文献   

19.
The crystal and molecular structure of 6-(p-iodobenzenesulfonyl)-3-oxa-6-azabicyclo-[3.1.0]hexane has been determined by a three-dimensional single-crystal x-ray diffraction study. The compound crystallizes in the monoclinic space group C2/c with cell dimensions, a = 19.76, b = 8.17, c = 15.72 ± 0.003 Å and β = 109.3° ± 0.2°. The aziridine ring is fused cis to the oxa-cyclopentane ring with fusion angles of 112°. The bicyclic system is in the boat conformation with the p-iodobenzenesulfonate group at an angle of 98.0° to it. The conformation of the ring system is discussed. A final value of R = 0.099 was obtained for the 1107 independent reflections.  相似文献   

20.
<正> [Me4N]6[Ag6(i-mnt)6].H2O(1),[Et4N]4[Cu8(i-mnt)6](2) and [Me4N]4-[Cu5Ag3(i-mnt)6].H2O(3)(i-mnt=S2C=C(CN)2) were synthesized. The crystal and molecular structure of the complex 1 was reported by us.The structure of the complex 2 was determined from single crystal X-ray diffraction data. [Et4N]4[Cu8(i-mnt)s] 2, Mr=1870.46, monoclinic, P21/n, a=14.724(6), b = 17.228(3), c=15.59(1)A,β= 100.75(7)°,V=3886.3A3;Z = 2,Dc= 1.598 g/cm3. Complex 3 has been characterized by ICP elemental analyses and IR spectrum.  相似文献   

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