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1.
The clusters Fe2Ru(CO)12–n (CNBu t ) n (3, n=1; 4, n=2), FeRu2(CO)12–n (CNBu t ) n (5, n=1, 6, n=2) and FeRu2(CO)11(CNCy) (5a) have been prepared by direct substitution from the parent carbonyl precursors Fe2Ru(CO)12 (1) and FeRu2(CO)12 (2). All compounds have been characterized spectroscopically and clusters 3, 4, 5, and 6 by single crystal X-ray determinations. In all cases, the isonitrile ligands adopt axial or pseudo-axial positions on a ruthenium atom. The structures of 35 are very similar to their parent clusters, but the extent of metal framework disorder is significantly less. Cluster 6 adopts the same C 2v Fe3(CO)12 type structure as 4, and thus differs markedly from the parent compound 2, which has a D 3 structure .  相似文献   

2.
《Liquid crystals》2012,39(15):2269-2280
ABSTRACT

Two homologous series of the three-ring azo/ester compounds 2-(or1-) naphthyl 4?-(4?’-alkoxy phenylazo) benzoates (Ina and IIna) were synthesised. A lateral methyl group was introduced in different positions of the alkoxy phenyl moiety, in position-2 to give series Inb and IInb and in position-3 to give series Inc and IInc. Molecular structures were characterised via elemental analyses, infrared and 1H-NMR. Their mesophase characteristics were investigated by differential scanning calorimetry (DSC) and their phases identified via polarised light microscopy (PLM). Transition temperatures were correlated with the alkoxy-chain length (n) that varies between 6, 8, 10, 12, 14, and 16 carbons. Comparative studies were first made to investigate the effect of including the extra fused benzene ring, and its orientation, into the previously investigated three-ring compounds, 4-phenyl 4?-(4′′-alkoxyphenylazo) benzoates (IIIna). Investigation of the mesophase behaviour was extended to cover the effect of introducing the lateral methyl group and its position. The comparison between the present six series and their corresponding phenyl analogues IIIna,b,c, indicated that the 2-naphthyl analogues, Ina,b,c, exhibit the highest mesophase stability. Whereas, the steric effect of the protruded naphthalene group destabilises all mesophases and appear only monotropically. The results were discussed in terms of polarisability effect.  相似文献   

3.
New organotin(IV) carboxylates, [n-Bu2SnL2] (1), [Et2SnL2] (2), [Me2SnL2] (3), [n-Oct2SnL2] (4), [n-Bu3SnL] n (5), [Me3SnL] n (6), and [Ph3SnL] n (7), where L?=?3-(4-bromophenyl)-2-ethylacrylate, were synthesized and characterized by elemental analysis, FT-IR, and multinuclear NMR (1H, 13C, and 119Sn). Spectroscopic studies confirm coordination of L to the organotin moiety via COO group. Single-crystal X-ray analysis reveals bridging mode of coordination in 6. Packing diagram established a supramolecular cage-like structure for 6 due to Sn–O interactions (3.287?Å). Subsequent antimicrobial activities proved them to be active biologically.  相似文献   

4.
A series of new complexes with mixed ligands of the type [ML(C3H3O2)2nH2O (((1) M=Mn, n=1; (2) M=Co(II), n=2; (3) M=Ni(II), n=4; (4) M=Cu(II), n=1.5; (5) M=Zn(II), n=0; L=3-amino-1,2,4-triazole and (C3H3O2)=acrylate anion) were synthesized and characterised by chemical analysis and IR data. In all complexes the 3-amino-1,2,4-triazole acts as bridge while the acrylate acts as bidentate ligand except for complex (5) where it is found as unidentate. The thermal behaviour steps were investigated in nitrogen flow. The thermal transformations are complex processes according to TG and DTG curves including dehydration, acrylate ion and 3-amino-1,2,4-triazole degradation respectively. The final products of decomposition are the most stable metal oxides, except for complex (4) that leads to metallic copper.  相似文献   

5.
The thermal reaction of Ru3(CO)12 with the saturated fatty acids (heptanoic, nonanoic, decanoic, tridecanoic, tetradecanoic, heptadecanoic, octadecanoic) in refluxing tetrahydrofuran, followed by addition of triphenylphosphine (PPh3) or pyridine (C5H5N), gives the dinuclear complexes Ru2(CO)4{OOC(CH2) n CH3}2L2 (1: n = 5, 2: n = 7, 3: n = 8, 4: n = 11, 5: n = 12, 6: n = 15, 7: n = 16; a: L = NC5H5, b: L = PPh3). The single crystal structure analysis of 1b, 2a, 3a, 4a and 5a reveals a dinuclear Ru2(CO)4 sawhorse structure, the diruthenium backbone being bridged by the carboxylato ligands, while the two L ligands occupy the axial positions at the ruthenium atoms. In 2a, π-π stacking interactions between adjacent pyridyl units of symmetry related molecules prevail, while in the longer alkyl chain derivatives 3a, 4a and 5a, additional van der Waals and electrostatic interactions between the alkyl chains take place as well in the packing arrangement of the molecules, thus giving rise to layers of parallel alkyl chains in the crystal.  相似文献   

6.
《Liquid crystals》2012,39(15):2322-2333
ABSTRACT

Two homologous series of the three-ring 4?-(4"-alkoxy-2"-(or 3")fluoro phenylazo) benzoates terminated with 2-(or 1-) naphthyl groups (Ind&e or IInd&e), respectively, were prepared and their mesophase behaviour investigated via differential scanning calorimetry, whereas the type of the mesophase identified by polarised light microscopy. Molecular structures of compounds prepared were first characterised via infrared, 1H-NMR and elemental analyses. Transition temperatures were correlated with the alkoxy chain length (n) that varies between 6, 8, 10, 12, 14 and 16 carbons.

Comparative studies were made to investigate the effect of including the lateral fluorine atom, and its orientation, into the previously investigated fluorine-free analogues, namely, 2-(or 1-) naphthyl 4?-(4"-alkoxyphenylazo) benzoates (Ina and IIna). The study was extended to investigate the effect of replacing the methyl group in the previously prepared 2"- and 3"-methyl analogues (Inb&c or IInb&c) with the fluorine atoms on their mesophase behaviour.  相似文献   

7.
The syntheses of 1∶1‐macrocycles 3 (n=1), unsymmetrical macrocycle 5 (m=0, n=1), 2∶2‐macrocycle 5 (m=n=1 and 2), 3∶3 macrocycle 7, and several open‐chain ethereal compounds prepared from 2,5‐dichloro‐1,3,4‐thiadiazole 1 and various polyethylene glycols dianions are described. Structural proofs are afforded by their mass and NMR spectral features. The quaternization studies of a few macrocycles with methyl iodide at elevated temperature furnished a diketo derivative 8 through a facile Hilbert–Johnson reaction.  相似文献   

8.
Novel porphyrin derivatives with twelve flexible alkyl chains, namely meso‐tetra[4‐(3,4,5‐n‐trialkoxybenzoylamino)phenyl]porphyrins (1a, n = 12; 1b, n = 16) and the zinc complex (2a) were synthesized. The mesomorphic properties were investigated by DSC, WAXD and polarizing optical microscopy; the results showed that 1a and 2a exhibit a pseudo‐hexagonal columnar phase, and 1b a rectangular (Col) phase over a wide temperature range including room temperature.  相似文献   

9.
The composition of the products obtained in the reactions ofn-BuMgBr andn-BuLi with cyclodecanone (1) has revealed that1 exhibits the properties of a sterically hindered ketone. The highest yield of 1-butylcyclododecanol (2) was achieved with the use ofn-BuMgBr, but in this case cyclododecanol was also formed, whereas the use ofn-BuLi led to the tertiary alcohol more distinctly. Dehydration of alcohol2 resulted in a mixture of three olefins containing up to 90 % ofE- andZ- isomers of 1-butylcyclododecene.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 907–909, May, 1993.  相似文献   

10.
Hydrolysis of pure Sb(OPri)3 by sol–gel method followed by sintering at 500 °C yields microcrystallites of Sb2O3 (senarmonite phase). Under similar conditions bimetallic alkoxide, [NaSb(OPri)4], yields a mixture of binary oxides Sb2O3 and Sb2O4. Chemical modification of Sb(OPri)3 with oximes forms monomeric products of the type [Sb(OPri)3−n {ON=C(CH3)R} n ] {where R = CH3, n = 1 [1]; n = 2 [2]; n = 3 [3]; R = 2-C5H4N, n = 1 [4]; n = 2 [5]; n = 3 [6]; R = 2-C4H3O, n = 1 [7]; n = 2 [8]; n = 3 [9]; R = 2-C4H3S, n = 1 [10]; n = 2 [11]; n = 3 [12]}. The liquid products [1–3, 7 & 10] were purified by distillation while the solids by recrystallization. All these products were characterized by elemental analyses, IR, NMR (1H and 13C{1H}) and representative derivatives [1], [2] and [3] by FAB mass studies. On the basis of these studies, a distorted pyramidal structure for all the derivatives may be assumed in the solution state containing an end-on coordination of oximes with the metal atom. Hydrolysis of the distilled precursors [1], [2] and [3] under sol–gel conditions yields pure nano-sized α-Sb2O4. All the oxides were characterized by XRD, SEM and EDX analysis exhibiting minimum particle size for the oxide obtained from the precursor [3].  相似文献   

11.
Solvothermal reactions of CuX (X?=?Br, SCN, CN) with bis(4-phenyl-pyrazol-1-yl)methane (phpzm) gave two 2-D coordination polymers, [Cu(μ-Br)(μ-phpzm)] n (1) and [{Cu(μ-SCN)}2(μ-phpzm)] n (2), and a 1-D coordination polymer, [(phpzm)Cu(μ-CN)] n (3). Compounds 13 were characterized by elemental analysis, IR spectra, and X-ray crystallography. Compounds 1 and 2 have 2-D networks in which split-stair [Cu(μ-Br)] n chains (1) or staircase-like [Cu(μ-SCN)] n double chains (2) are linked by μ-phpzm bridges. Compound 3 consists of a zigzag chain formed by linking [Cu(phpzm)] fragments via cyanide bridges. Luminescence properties of 13 along with phpzm in the solid state at ambient temperature were also investigated.  相似文献   

12.

Abstract  

Three new cadmium coordination polymers, [CdBr2(tmdp)2(μ-tmdp)2] n ·n(H2O) (1), [Cd(SCN)2(μ-tmdp)2] n ·2n(PhS) (2) and [Cd(SCN)2(μ-tmdp)2] n ·n(Ph2S2n(CH3CN) (3) (tmdp = 4,4′-trimethylenedipyridine), have been synthesized under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analysis. The geometry around cadmium is a slightly distorted octahedron with four tmdp and two Br- or SCN- ligands. Complex 1 represents a one-dimensional structure, whereas complexes 2 and 3 are two-dimensional coordination polymers. The rhombic channels of the coordination network of 2 and 3 are occupied by 1D polymeric (PhS) n and diphenyl disulfide (Ph2S2) molecules, respectively. The photoluminescent properties of coordination polymers 13 were investigated in solid state at room temperature. The TGA experiments showed that these three complexes were quite thermally stable.  相似文献   

13.
Four monomeric [n-Bu2SnL2 (1), Et2SnL2 (2), Me2SnL2 (3), and n-Oct2SnL2 (7)] and three polymeric {[n-Bu3SnL]n (4), [Me3SnL]n (5), and [Ph3SnL]n (6)} organotin(IV) carboxylates, where L?=?4-chlorophenylethanoate, were synthesized and characterized by elemental analysis, FT-IR, and multinuclear NMR (1H, 13C, and 119Sn). Compounds 2 and 5 were also analyzed by X-ray single-crystal analysis showing monomeric and zigzag structures, respectively. Two types of O…H (2.641?Å) and Cl…H (2.943?Å) non-covalent interactions generate a 2-D supramolecular structure for 2. Layer-by-layer supramolecular structure was observed for 5 in which polymeric chains are connected via non-covalent interactions {Cl…H (2.869?Å), H…π (2.899?Å)}, and unconventional dihydrogen {H…H (2.381?Å)} interactions.  相似文献   

14.
A series of LnIII–SrII heterometallic coordination polymers formulated as [Ln2Sr3(pda)6(H2O)18]·nH2O (Ln = Pr-1, n = 14; Nd-2, n = 12; Sm-3, n = 11; Eu-4, n = 11; Gd-5, n = 16; Tb-6, n = 13; Dy-7, n = 13) were synthesized via assembly of Ln(NO3)3·6H2O, SrCl2·6H2O, pyridine-2,6-dicarboxylic acid (H2pda) and imidazole (im) in H2O/C2H5OH solution. Single crystal X-ray diffraction revealed that they are isostructural. All of these complexes possess ladder-shaped 1-D chain structures. The luminescent properties of Sm-3, Eu-4, Gd-5, Tb-6 and Dy-7 have been investigated. The solid-state quantum yields and the lifetimes of Eu-4 and Tb-6 are also studied.  相似文献   

15.
Abstract

Vibrational spectra of (CH3O) n SbCl5–n . n = 1: 1; n = 2: 2: n = 3: 3: n = 4: 4; n = 5: 5; have been recorded. According to ir and Raman data 1–5 are centrosymmetrical bridged dimers. The Raman spectra of 3–5 exhibit v(Sb–O) doublets of terminal CH3O at 530–541 and 550–570 cm?1; vibrations of the 4-membered Sb2O2 ring, observed in the 500–517 cm?1 region of the ir spectra of 1–5, are absent. The v(C–O) bands of bridged and terminal CH3O are shifted to higher wave numbers (60 and 31 cm?1, respectively) in the series 15. The stability of the dimers increases in the series 1 < 2 < 3 < 4 ? 5. At 100–120°C and in CH3CN solutions dimers of 1–3 dissociate to monomers (v(Sb–O) 537–540 cm?1, ir data). The monochloride, 4, is partially dissociated in CH3CN. On solution of the tetrachloride, 1, in benzene a dimer-monomer equilibrium has been observed, with the dimeric form being predominant.  相似文献   

16.
苯丙炔酸和苯丙烯酸酯苯并菲盘状液晶的合成及介晶性   总被引:2,自引:0,他引:2  
合成了7个含苯丙炔酸和苯丙烯酸酯链的苯并菲盘状液晶化合物C18H6(OCnH2n+1)5O2CR' [R'=C≡CC6H5, n=4~9 (1a1f); R'=CH=CHC6H5, n=6 (1g)]. 该系列化合物结构通过1H NMR, IR和元素分析表征. 液晶性通过差示扫描量热法和偏光显微镜进行了研究, 结果显示: 化合物均为六方柱状相热致型液晶; 含苯丙炔酸酯链苯并菲盘状液晶化合物1a1f, 随着烷氧链的增长, 清亮点呈现逐渐下降的趋势; 对于含苯丙烯酸酯链苯并菲化合物1g与具有同样软链长度的炔基酯链苯并菲化合物1c比较, 具有更低的熔点和结晶点, 而它们的清亮点几乎一致, 因而化合物1g有更宽的介晶性温度范围.  相似文献   

17.
Abstract

Die Spaltung von s-Trithian, Trithioacetaldehyd, (CH2S) n und (CH2S2) n mit Natrium in flüssigem Ammoniak liefert Mercaptothioether und Bis-Mercaptothioether nach einem allgemien anwendbaren Reaktionsprinzip. Beschrieben wird die Synthese von 2.4-Dithiapentan-1-thiol (1), 2-Thiapropan-1-thiol (2), 2-Mercapto-3-thiapentan (4) und Bis-mercaptodimethylsulfid (6).

The cleavage of s-trithiane, trithio acetic aldehyde, (CH2S) n and (CH2S2) n by sodium in liquid ammonia leads to the formation of mercapto thioethers and bis-mercapto thioethers according to a general reaction principle. Described is the synthesis of 2.4-dithiapentane-1-thiole (1), 2-thiapropane-1-thiole (2), 2-mercapto-3-thiapentane (4) and bis-mercapto dimethyl sulfide (6).  相似文献   

18.
The complexes of the type M(HDMBG)2(CH3COO)2·nH2O ((1) M:Mn, n=1.5; (2) M:Ni, n=0; (3) M:Cu, n=2; (4) M:Zn, n=2; DMBG: N,N-dimethylbiguanide) present in vitro antimicrobial activity. The thermal analysis has evidenced the thermal intervals of stability and also the thermodynamics effects that accompany them. The different nature of the ligands generates a different thermal behaviour for the complexes. The thermal transformations are complex processes according to TG and DTG curves including dehydration, oxidative condensation of –C=N– units as well as thermolysis processes. The final products of decomposition are the most stable metal oxides.  相似文献   

19.
[Co2(TTBT)4(1,2-BDC)2] n ?·?4nH2O (1), [Pb2(TTBT)2(1,3-BDC)2] n ?·?nTTBT?·?2nH2O (2), [Fe(TTBT)(1,4-BDC)(H2O)] n (3), and [Zn(TTBT)(1,4-BDC)(H2O)] n (4) have been hydrothermally synthesized by self-assembly of TTBT (TTBT?=?10,11,12,13-tetrahydro-4,5,9,14-tetraaza-benzo[b]triphenylene), benzene-dicarboxylic acid ligands 1,2-H2BDC, 1,3-H2BDC or 1,4-H2BDC (1,2-H2BDC?=?1,2-benzenedicarboxylic acid, 1,3-H2BDC?=?1,3-benzenedicarboxylic acid, 1,4-H2BDC?=?1,4-benzenedicarboxylic acid), and various metal salts. Compound 1 has dinuclear cluster units, four dimeric Co2 units connected to form a 32-membered ring via weak offset π–π interactions, which are further stacked via strong π–π interactions to form a 3-D supramolecular framework. Complex 2 contains 2-D layers with rhombohedral grids, which are connected to a 3-D structure by π–π interactions. 3 and 4 feature 1-D infinite chains, which are further extended by strong π–π interactions and O–H···O hydrogen bonds resulting in 3-D supramolecular architectures. The photoluminescent properties of 2 and 4 have also been investigated.  相似文献   

20.
用三烯烃三吡啶配体1,3,5三-((4-吡啶)-1,2-乙烯基)苯(tpeb)和M(NO_3)_2(M=Co,Ni,Zn,Cd)以及4种不同的有机羧酸(3,5-二溴苯甲酸(3,5-HDBB)、2,5-噻吩二羧酸(2,5-H_2TDC)、2,5-呋喃二羧酸(2,5-H_2FDC)、2,5-二溴对苯二甲酸(2,5-H_2DBTP))进行溶剂热反应,得到了[Zn(tpeb)(3,5-DBB)_2]_n(1)、[Co_2(tpeb)_2(2,5-TDC)_2]_n(2)、[Co_2(tpeb)_2(2,5-FDC)_2]_n(3)、[Co(tpeb)(2,5-DBTP)]_n(4)、[Ni(tpeb)(2,5-DBTP)]_n(5)、[Cd(tpeb)_(0.5)(2,5-DBTP)]_n(6)六个配位聚合物。对配合物1~6分别进行了单晶X射线衍射、粉末X射线衍射、红外、元素分析、热重、荧光等结构表征。配合物1~6结构独特且多样。配合物1是由[Zn(3,5-DBB)_2]单元通过配体tpeb桥联构筑的一维zigzag链状结构;配合物2和3是由一维梯状[Co(tpeb)]_n链分别与2种不同的五元杂环二取代羧酸桥联构筑而成的二维双层结构;配合物4和5均是由一维[M(2,5-DBTP)]_n(M=Co,Ni)链通过tpeb交叉连接而成的三维网络结构;配合物6则是由二维的[Cd(2,5-DBTP)]_n层状结构通过tpeb连接而成的三维互穿拓扑网络结构。配合物1~6的热稳定性较好,它们在固态时表现出不同的荧光性质。  相似文献   

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