4-(2,5-二甲基-3,4-二乙酰基)-1-吡咯基苯甲酸的合成及其晶体结构

在强酸性介质中,3,4-二乙酰基-2,5-己二酮与对氨基苯甲酸作用,满意地得到了4-(2,5-二甲基-3,4-二乙酰基)-1-吡咯基苯甲酸,用IR、1H NMR、高分辩质谱等对其进行了表征,用X射线衍射测定了晶体结构.该晶体属三斜晶系,P1空间群,a＝0.80950(10)nm,b＝0.81910(10)nm,c＝1.1900(2)nm,α＝101.600(10)°,β＝98.820(10)°,γ＝104.960(10)°,Z＝2,Dc＝1.364×103kg/m3.拟合了苯环平面和吡咯环平面的平面方程,并求出两平面之间的二面角为68.11°.     

2,5-二甲基-3,4-二乙酰基-1-(3-硝基苯基)吡咯的合成及晶体结构

在酸性介质中,3,4-二乙酰基-2,5-己二酮与硝基苯胺作用,满意地得到了2,5-二甲基-3,4-二乙酰基-1-(硝基苯基)吡咯,用IR、1HNMR、高分辨质谱等对其进行了表征,并用X射线衍射测定了2,5-二甲基-3,4-二乙酰基-1-(3-硝基苯基)吡咯的晶体结构.该晶体属单斜晶系,P21/c空间群.晶体学数据如下:a＝0.9375(1)nm,b＝1.2814(2)nm,c＝1.2985(1)nm,β＝100.96(1)°,V＝1.5315(3)nm3,Z＝4,M＝300.31,Dc＝1.302×103kg/m3.     

2,5—二甲基—3,4—二乙酰基—1—（3—硝基苯基）吡咯的合成及晶体 …

在酸性介质中,３,４－二乙酰基－２,５－己二酮与硝基苯胺作用,满意地得到了２,５－二甲基－３,４二乙酰基－１－（硝基苯基）吡咯,用ＩＲ、＾１ＨＮＭＲ、高分辨质谱等对其进行了表征,并用Ｘ射线衍射测定了２,５－二甲基－３,４－二乙酰基－１－（３－硝基苯基）吡咯的晶体结构。该晶体属单斜晶系,Ｐ２１／Ｃ空间群。晶体学数据如下：ａ＝０．９３７５（ａ）ｎｍ,ｂ＝１．２８１４（２）ｎｍ,ｃ＝１．２９８５（１）ｎ     

2,2'-(3,硝基4-氯苯基)次甲基双(3-羟基-5,5-二甲基-2-环己烯-1-酮)合成与晶体结构

以3-硝基-4-氯苯甲醛和5,5-二甲基-1,3-环己二酮为原料,二甲基甲酰胺为溶剂,不需催化剂合成一种新的氧杂蒽二酮开环衍生物2,2'-(3-硝基-4-氯苯基)次甲基双(3-羟基-5,5-二甲基-2-环己烯-1-酮)晶体,确定最佳反应条件是:芳醛和脂肪环酮的摩尔投料比为1∶2,反应温度为80℃,反应时间为lh;并对其进行熔点、元素分析、红外光谱、氢核磁共振及X-射线单晶衍射测定.该晶体为单斜晶系,空间群=P21/n,a=1.95777(13)nm,b=1.22720(9) nm,c=1.99687(14) nm,β=107.719(2).,V=4.5700(6) nm3,Z=8,dc=1.302 g/m3,μ =0.205mm-1,F(000)=1888.     

2-甲基4-(4-(吡啶-3-乙炔基)苯基)-3-丁炔-2-醇的合成及晶体结构

由1,4-二碘代苯出发,经过两步Sonogashira偶联反应合成了标题配合物2-甲基4.(4-(吡啶-3-乙炔基)苯基)-3-丁炔-2-醇.通过1H NMR、13C NMR核磁共振、Ⅹ-射线单晶衍射等手段对化合物的结构进行了表征.结果表明,该化合物晶体属于单斜晶系,空间群为P21/c.晶体学参数:a=3.3321 (4) nm,b=1.00539(11) nm,c=0.89158(10) nm,α =90.00°,β=92.442(2)°,y=90.00°,V=2984.2(6) nm3,Z =4.     

基于2,5-二溴对苯二甲酸配体的锌/钴配合物合成、晶体结构及性质

将有机物2,5-二溴对苯二甲酸(H₂L₁)和2,2′-联吡啶(L₂)作为双配体,使用溶剂热法和七水合硫酸锌(ZnSO₄·7H₂O)、六水合硝酸钴(Co(NO₃)₂·6H₂O)分别反应,得到配合物[Zn(L₁)(L₂)(H₂O)]_n(1)和配合物[Co(L₁)(L₂)(H₂O)]_n(2)。采用单晶X射线衍射、元素分析、红外光谱、紫外光谱、荧光光谱、热重分析等测试方法对这两种物质进行分析研究。单晶测试结果表明配合物1是单斜晶系,以Zn²⁺配位连接L^2-₁与L₂形成一维链状结构,各条链在分子间氢键和π…π共轭作用下有规律地堆叠形成三维网络结构。配合物2是三斜晶系,Co1离子和Co1ⁱ离子由H₂L₁上的羧酸氧原子O4和O4ⁱ连接,形成双齿螯合的配位结构单元,以Co²⁺配位连接 L^2-₁和L₂形成二维网格结构,各层在O—H…O分子间氢键和范德瓦耳斯力作用下有规律的堆叠形成三维网络结构。配合物1和2均含有芳香杂环、羧基杂环和氮杂环,具有良好的荧光性质和热稳定性,最大发射波长分别为345 nm和333 nm。     

以2-甲基-丙烯酸,4-(吡啶-4-偶氮)-苯酯为配体的四个配位化合物的合成、晶体结构和紫外吸收

4个单核配位化合物,[Zn(Maape)2(H2O)2(NO3)2] (1, 单核), [Cu(Maape)2(H2O)2(NO3)2] (2, 单核), [Zn(Maape)2Cl2] (3, 单核), [Zn(Maape)(H2O)4SO4] (4, 单核),都是用过渡金属盐和配体2-甲基-丙烯酸,4-(吡啶-4-偶氮)-苯酯合成的.四个化合物由单晶X-射线衍射和结构分析表明都是单核化合物.另外,还通过红外和元素分析对其进行表征.配位化合物的结构不仅受配位金属离子的影响还受不同配位阴离子的影响.化合物1和2的结构都是由一个金属离子中心、2个配位硝酸根离子和2个配体分子组成的单核配合物.化合物3的单核结构中包含一个Zn(II)、2个氯离子和2个配体分子.而化合物4的不对称单元[Zn(Maape)(H2O)4SO4]中Zn(II)中心位于二重对称轴上.在本文中,配体和4个化合物都在323 nm处有最高紫外吸收峰.     

基于3-羟基-2-吡啶苯甲酸的铜(Ⅱ)配位聚合物的合成,晶体结构和光催化性能

以3-羟基-2-吡啶苯甲酸(H2L)和Cu(NO3)2·6H2O为原料,通过溶剂热反应得到了一个新的配位聚合物[Cu(HL)2·C2H5OH]n(1).通过X-射线单晶衍射、元素分析、红外光谱(FT-IR)、热重分析(TG-DTA)和固态漫反射光谱(UV-Vis)等实验手段对配合物进行了表征.结果表明,配合物1结晶于单斜晶系,P21/c空间群.最小结构单元中包含一个铜离子与四个有机配体,形成六配位模式,并进一步通过有机配体的羧基和羟基基团桥接,形成了二维平面结构.配合物1具有半导体性质,带隙能(Eg)为3.01 eV.光催化性能测试结果表明,配合物1对染料亚甲基蓝(MB)和甲基橙(MO)均具有催化降解效果,在紫外光照射下120 min和180 min内,对二者的降解率分别为92.6;和45.4;.配合物1还具有良好的循环再生性,重复使用5次后仍能保持对MB分子的光催化活性基本不变.     

2,5-二羟基对苯二甲酸Tb(Ⅲ)配位聚合物的合成与表征

采用溶剂热法合成了一个配位聚合物{[Ln2(H2-DHBDC)3(H2O)4] (H2O)2}n(H2-DHBDC=2,5-二羟基对苯二甲酸).利用X-射线单晶衍射(SCXRD)、元素分析(EA)、红外光谱(FTIR)、热重分析(TG)和荧光分光光度法(FS)等对其结构和性质进行了分析与表征.结果表明:晶体属于单斜晶系,P-1空间群,晶胞参数a=1.0640(8)nm,b=1.1239(9) nm,c=1.5232(12) nm,α =99.351(11)°,β=99.511(11)°,γ=92.482(12)°,V=1768(2) nm3,Z=2.八个氧原子在铽离子周围形成一个变形的三角十二面体配位环境,金属离子通过与配体连接形成具有一定孔道的三维结构.荧光分析测试表明,配合物具有较好的荧光性.     

5-溴-2-(4-甲基哌啶-1-基)嘧啶的晶体结构及密度泛函理论研究

嘧啶类衍生物在医药、化工和功能材料等领域有着重要应用。在药物研发,特别是抗癌药物研发领域中,5-溴-2-(4-甲基哌啶-1-基)嘧啶是一种含嘧啶环的重要中间体。本文通过一步芳香亲核取代反应合成了5-溴-2-(4-甲基哌啶-1-基)嘧啶,经溶液结晶法获得其单晶体,并进行了晶体学分析(晶系:正交晶系,空间群:P2₁2₁2₁,晶胞:a=10.181 42(6) nm, b=17.620 0(8) nm, c=10.179 02(5) nm,Z=4,ρ_c＝1.478 g·cm^-3,R=0.056 6,wR=0.168 8)。标题化合物的最优结构和前线轨道能量在B3LYP/6-311G(d, p)模式下使用密度泛函理论(DFT)计算得到,经DFT优化的结果与实验确定的数据相近。此外,为进一步揭示标题化合物的物理化学性质,通过DFT进一步研究了分子的静电式和前线分子轨道。     

Synthesis,Crystal Structure and Spectroscopy of 3,4-Perylene-dicarboxylic Monoanhydride

The preparation, via a chemical vapor deposition process, of metallic-green whiskers of 3,4-perylenedicarboxylic monoanhydride (PDCMA), is described. The crystal structure and the electronic, infrared and resonance-enhanced Raman spectra of the PDCMA crystals are reported and compared with the corresponding data for the dianhydride, PTCDA. Interesting differences in the spectroscopy of PDCMA compared with that of PTCDA have been found. This has been correlated with the somewhat increased charge delocalization in PDCMA caused by the packing of the molecules in the crystal. The application of some of these results in characterizing the partly solid state, heat-induced polymerization of PTCDA to the intrinsically conducting polymer, polyperinaphthalene, is also pointed out.     

Crystal and molecular structure of 2,5-dimethyl-3,4-diacetylpyrrole

An X-ray crystallographic study of 2,5-dimethyl-3,4-diacetylpyrrole showed that the crystals are monoclinic, space groupP2₁/n,a = 10·01(3),b = 12·93(3),c = 7·41(2) Å and = 91·5(5) °. The crystal structure was solved by direct methods and refined by least squares to a finalR factor of 0·13. The values determined for the bond distances and angles of the pyrrole ring are in good agreement with the values reported in the literature. However, there are significant changes in the exocyclic bond angles of the atoms of the ring. The planes of the acetyl groups are tilted with respect to the ring plane, forming dihedral angles of 22 ° and 40 °.     

Crystal and molecular structure of 2,5-dimethyl-3,4-diacetylfuran

The crystal and molecular structure of 2,5-dimethyl-3,4-diacetylfuran has been determined by direct methods using CuK. photographic data. Refinement by full-matrix least-squares methods gave a finalR factor of 0·097. The crystals are monoclinic: space groupP2₁/c,a =14·92(2),b = 4·09(1),c =16·68(3) Å and = 109·7(5) °;Z = 4. The furan ring of the molecule is planar, and the exocyclic atoms bound to the atoms of the ring lie close to the ring plane. The planes of the acetyl groups are tilted by 16 ° and 47 ° with respect to the ring plane. The exocyclic bond angles of this compound are significantly different from the equivalent angles in furan.     

Synthesis and structural characterization of 2,5-dihalo-3,4-dinitrothiophenes

Using new nitration protocols, we have been able to efficiently dinitrate 2,5-dihalothiophenes with yields of ～80–95%. The resulting products 2,5-dibromo-3,4-dinitrothiophene (1), 2,5-dichloro-3,4-dinitrothiophene (2), 2-bromo-5-chloro-3,4-dinitrothiophene (3), as well as the analogous 2-bromo-3,4-dinitrothiophene (4), all crystallize easily allowing their characterization via X-ray crystallography. Crystallization of 1 occurs in the monoclinic space group C2/c with a = 14.547(3) Å, b = 7.3534(15) Å, c = 10.775(2) Å, β = 128.89(3)°, and Z = 4. Crystallization of 2 occurs in the tetragonal space group I-42d with a = 9.9398(14) Å, b = 9.9398(14) Å, c = 16.866(3) Å, and Z = 8. Crystallization of 3 occurs as a pseudo-merohedral twin in the triclinic space group P-1 with a = 7.340(5) Å, b = 8.094(5) Å, c = 9.112(5) Å, α = 82.059(5)°, β = 66.232(5)°, γ = 63.021(5)°, and Z = 2. Crystallization of 4 occurs in the triclinic space group P-1 with a = 7.1787(14) Å, b = 7.4092(15) Å, c = 8.3151(17) Å, α = 101.67(3)°, β = 96.00(3)°, γ = 116.13(3)°, and Z = 2. The structures of all compounds exhibit the formation of interesting solid-state assemblies due to halogen-bonding interactions between the halogen and nitro groups.     

Synthesis and Crystal Structure of Heptyl 3-(3,4-dihydroxyphenyl)-2-propenoate

Abstract  The title compound, C₁₆H₂₂O₄, synthesized by modified Knoevenagel condensation of protocatechualdehyde with monoheptyl-malonate and recrystallized from benzene, was confirmed by single-crystal X-ray diffraction (CCDC 272827). The compound crystallizes in triclinic space group Pī with cell parameters a = 5.296(3) ?, b = 10.711(13) ?, c = 13.870(4) ?, α = 98.84(7)°, β = 90.97(4)°, γ = 96.77(7)° and Z = 2. The structure is the E isomer and its packing is stabilized by intermolecular O–H···O and C–H···O hydrogen bonds. Index Abstract  The title compound, C₁₆H₂₂O₄, synthesized by modified Knoevenagel condensation, was confirmed by single-crystal X-ray diffraction showing its structure is in E isomer and its packing is stabilized by hydrogen bonds.      

Crystal Structure of Liguzinediol, 2,5-Dimethylol-3,6-dimethylpyrazine

The 2,5-dimethylol-3,6-dimethylpyrazine, C₈H₁₂N₂O₂, liguzinediol, has been recently discovered as a potential agent for the treatment of heart failure with low safety risk. The crystal structure of liguzinediol, which has been determined by single-crystal X-ray diffraction analysis, is reported for the first time. The liguzinediol crystal may be obtained from 50% ethanol or ethyl acetate. The compound crystallizes in the monoclinic system with the sp. gr. P2₁/n and the unit cell parameters a = 4.0560(8) Å, b = 12.280(3) Å, c = 8.5370(17) Å, β = 96.93(3)°, Z = 2. The molecule forms S₂-symmetric conformation in the crystal. The hydroxyl H atom forms short intermolecular contacts with the neighbouring pyrazine N atom, which forms the weak hydrogen bonds in the crystal.     

Synthesis and Crystal Structure of NdCaGaO4

The crystal structure of the NdCaGaO₄ compound was investigated by means of X-ray structure analysis (powder diffractometer HZG-4, CuK_α): structure type LaCuO₄, space group Cmca, a = 5.3700(2) Å, b = 12.1058(3) Å, c = 5.3937(2) Å, Z = 4, R_I = 0.126. The shortest interatomic distances are: Nd(Ca)—O — 2.240(14) Å; Ga—O — 1.913(2) Å, O—O — 2.6852(2) Å, Nd(Ca)—Nd(Ca) — 3.442(3) Å, Nd(Ca)—Ga — 3.154(4) Å, Ga—Ga — 3.8056(2) Å. Atoms have the following coordination numbers: Nd(Ca) — 8; Ga — 6; O1 — 14(6); O2 — 9(5).