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1.
Palladium-catalysed Buchwald–Hartwig amination of ortho-substituted hindered aryl bromides or chlorides with 9H-carbazole has been investigated. In the amination of 1-bromo- or chloronaphthalene with 9H-carbazole, the combined use of Pd2(dba)3 as a Pd precursor, Buchwald ligands with two tert-butyl groups and LiOtBu or lithium hexamethyldisilazide as a base led to satisfactory yields. N,N’-Bis[2,6-bis(diphenylmethyl)-4-methoxyphenyl]imidazol-2-ylidene (IPr*OMe), which is a bulky N-heterocyclic carbene ligand, showed similar activity as Buchwald ligands with two tert-butyl groups. In contrast, only IPr*OMe provided satisfactory yields in the amination of 2-bromo-1,1′-biphenyl with 9H-carbazole. The amination of 2-bromo- or chlorotoluene and 1-(2-bromo- or chlorophenyl)naphthalene with 9H-carbazole proceeded smoothly when the IPr*OMe ligand was used.  相似文献   

2.
Four coordination polymers (CPs), [Cd(2,7-dpfo)2(NO3)2(CH3OH)]n (1) , [Zn(2,7-dpfo)(NO3)(CH3COO)]n (2) , [Co(2,7-dpfo)2(H2L)]n (3) , and [Ni(2,7-dpfo)2(H2L)]n (4) (where 2,7-dpfo is 2,7-di(pyridin-4-yl)-9H-fluoren-9-one and H4L is 1,1′:4′,1′′-terphenyl-4,2′,5′,4′′-tetracarboxylic acid), were synthesized and structurally characterized. Compounds 1 – 4 were determined by elemental analyses, single crystal X-ray diffraction analyses, powder X-ray diffraction, infrared spectroscopy, and thermogravimetric analyses. Compound 1 displays a one-dimensional (1D) zigzag chain structure, while compound 2 possesses a 1D ladder chain structure. Compounds 3 and 4 are isostructural and consist of 1D chains. The solid-state luminescent properties of 1 and 2 and the magnetic properties of 3 and 4 were also investigated.  相似文献   

3.
The functional polymer containing carbazole unit, [(poly(9-(4-vinylbenzyl)-9H-carbazole) (PVBK)], was successfully prepared via nitroxide-mediated living free-radical polymerization of 9-(4-vinylbenzyl)-9H-carbazole (VBK). The controlled features of the polymerization were confirmed by the linear increase in the molecular weight with the monomer conversion while keeping the relative narrow molecular weight distribution (Mw/Mn ? 1.51), and successful chain extension with styrene. The resulting polymer absorbed light in the 305-355 nm range and exhibited fluorescent emission at 350 nm. The fluorescent intensity of the polymer was lower than that of monomer and was affected by the properties of the different solvents, which decreased in the following order: DMF > THF > CHCl3 at the same concentration of carbazole units. The fluorescence intensity of the polymer was apparently influenced by chromophore concentration, and the maximum value was obtained when the carbazole unit concentration was around 8 × 10−5 mol/L. Moreover, it was shown that the strong fluorescence of PVBK can be quenched by methyl acrylate (MA).  相似文献   

4.
A novel fluorinated diamine monomer, 9,9-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]fluorene (II) was prepared via the nucleophilic substitution reaction of 2-chloro-5-nitrobenzotrifluoride with 9,9-bis(4-hydroxyphenyl)fluorene in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C. Polyimides V were synthesized from diamine II and various aromatic dianhydrides III a-f via thermal imidization. These polymers had inherent viscosities ranging from 0.84 to 1.03 dL/g and were soluble in a variety of organic solvents such as NMP, DMAc, DMF, and DMSO, and some could even be dissolved in less polar solvents such as m-cresol, pyridine, and dioxane. Polyimide films V a-f had tensile strengths of 85–105 MPa, elongations to break of 7–9%, and initial moduli of 2.13–2.42 GPa. The glass transition temperature of these polymers were in the range of 277–331 °C, their 10% weight loss temperatures were in the range of 539–594 °C in nitrogen and above 544 °C in air, and their char yields at 800 °C in nitrogen ranged between 55–65 wt%. Compared with nonfluorinated polyimides VI, V showed better solubility and lower color intensity. Low dielectric constants (2.68–2.85 at 1 MHz) and low moisture absorptions (0.12–0.24 wt%) were also observed. In particular, V c-f afforded lightly-colored films, which had cutoff wavelengths lower than 385 nm and b* values ranging from 6 to 22.  相似文献   

5.
9,9-Bis[4-(p-aminophenoxy)phenyl]fluorene ( II ) was used as a monomer with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to synthesize polyamides and polyimides, respectively. The diamine II was derived by a nucleophilic substitution of 9,9-bis(4-hydroxyphenyl)fluorene with p-chloronitrobenzene in the presence of K2CO3 and then hydro-reduced. Polyamides IV a-g having inherent viscosities of 0.73–1.39 dL/g were prepared by the direct polycondensation of the diamine II with various aromatic diacids using triphenyl phosphite and pyridine as condensing agents. All the aromatic polyamides were amorphous and readily soluble in various polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, and N-methyl-2-pyrrolidone. Transparent and flexible films of these polymers could be cast from the DMAc solutions. These aromatic polyamides had glass transition temperatures in the range of 283–309°C and 10% weight loss occurred up to 460°C. The polyimides were synthesized from diamine II and various aromatic dianhydrides via the two-stage procedure that included ring-opening poly-addition in DMAc to give poly(amic acid)s, followed by thermal or chemical conversion to polyimides. The poly(amic acid)s had inherent viscosities of 0.62–1.78 dL/g, depending on the dianhydrides. Most of the aromatic polyimides obtained by chemical cyclization were found to be soluble in NMP. These polyimides showed almost no weight loss up to 500°C in air or nitrogen atmosphere. © 1993 John Wiley & Sons, Inc.  相似文献   

6.
Cyclic 1,2-diphenylenediboranes containing a doubly hydrogen-bridged structure, including 1,2-(2,2biphenylylene)diborane(I) and 1,2-(2,2biphenylylene)-1,2-diethyldiborane (II), are conveniently prepared by treating 9-chloro-9-borafluorene with NaBH4 and Na(Et)3BH, respectively. The reaction mechanism involves an initial Cl-H exchange to form 9-borafluorene containing a reactive 5-member ring diarylborane moiety, which subsequently engages in a facile ring expansion with the in situ formed B-H containing residue (BH3 or HBEt2) to result in cyclic 1,2-diphenylenediboranes compounds. The doubly hydrogen-bridged structure shows good thermal stability up to 50 °C. Upon thermal cleavage at higher temperature, all free B-H groups become very reactive involving hydroboration with α-olefin. The complexization study also reveals that this intradiborane moiety forms a 1:2 complex with a strong base, such as pyridine.  相似文献   

7.
Summary The use of 2-(9-carbazole)ethyl chloroformate (CEOC) for pre-column derivatization of biogenic amines (BA) has been tested for the first time. The reagent reacts completely with BA within 3 min at ambient temperature in acetonitrile solution to form stable derivatives that are readily analyzed by reversed-phase HPLC. Study of the derivatization conditions revealed derivatization yields to be excellent in borate buffer over the pH range 9.0–10.0. Maximum yields were obtained by use of a three- to fourfold molar excess of reagent. The reaction is extremely tolerant of common buffer salts, no decrease in reaction yield is discernible in well-buffered samples. The emission maximum for the CEOC-derivatives is 360 nm (λ ex = 293 nm). All the derivatives fluoresced strongly and direct injection of the reaction mixture was possible, with no significant disturbance from the major fluorescent reagent degradation by-products, 2-(9-carbazole)ethanol (CEOC-OH) and bis-(2-(9-carbazole)ethyl) carbonate (CEOC)2. Separation of the derivatized BA by high-performance liquid chromatography with gradient elution was tested on a Hypersil BDS C18 column. Excellent response linearity was observed over the concentration range from 0.25 to 94.6 μmol L−1 for the labeled BA. Detection limits were 117–840 fmol at a signal-to-noise ratio of 3∶1. Analysis of BA in a shrimp sauce extract was conducted to demonstrate the applicability of the technique to real sample matrixes; results were satisfactory.  相似文献   

8.
New bidentate Schiff-base ligands 2-(2,4-di-p-tolyl-3-azabicyclo[3.3.1]nonan-9-ylidene)hydrazinecarbothioamide HL1 and 2-(2,4-di-p-tolyl-3-azabicyclo[3.3.1]nonan-9-ylidene)hydrazinecarboxamide HL2 were synthesized from the condensation of 2,4-di-p-tolyl-3-azabicyclo[3.3.1]nonan-9-one with thiosemicarbazide and semicarbazide, respectively. Homoleptic complexes of these ligands, of general formula K[Cr(L n )2Cl2], K2[Mn(L n )2Cl2], K2[Fe(L1)2Cl2] and [M(L n )2] (where M = Co(II), Ni(II) Cu(II), Zn(II), Cd(II), and Hg(II) ions; n = 1 or 2) are reported. The mode of bonding and overall geometry of the complexes were determined through IR, UV-Vis, NMR and mass spectral studies, magnetic moment measurements, elemental analysis, metal content, and conductance. These studies revealed octahedral geometry for Cr(III), Mn(II), and Fe(II) complexes, square planar for Cu(II), Co(II), and Ni(II) complexes and tetrahedral for Zn(II), Cd(II), and Hg(II) complexes.  相似文献   

9.
Zaijun L  You F  Zhongyun L  Jian T 《Talanta》2004,63(3):647-651
A spectrophotometric method was developed for the determination of iron(III)-dimethyldithiocarbamate (ferbam) by concerting it into an iron(III)-9-(4-carboxyphenyl)-2,3,7-trihydroxyl-6-fluorone complex. In NH3-HAc buffer solution (pH 6.5), the reagent reacts with ferbam to form a blue complex with a maximum absorption peak at 640 nm. The reaction can be completed rapidly at room temperature and the absorbance is stable for at least 24 h. The apparent molar absorption coefficient, Sandell’s sensitivity of the complex, the detection limit and the relative standard deviation were found to be 1.06×105 l mol−1 cm−1, 3.9 ng cm−2, 2.2 ng ml−1 and 1.06%, respectively. From 0 to 75 μg of ferbam in 25 ml solution the absorbance obeyed Beer’s law. The effect of foreign ions and other dithiocarbamates were also studied in detail. The results indicated that all coexisting ions examined can be tolerated in considerable amounts, especially other dithiocarbamates such as ziram and zineb, which always interfere with the determination of ferbam in the literature. The proposed method is very sensitive, selective and simple, it has been applied to determine ferbam in commercial samples.  相似文献   

10.
A pre-column derivatization method for sensitive determination of oligopeptides, using the tagging reagent 2-(9-carbazole)ethyl chloroformate (CEOC-Cl) followed by capillary electrophoresis (CE) with diode-array detection, has been developed. Maximum yield close to 100% were observed when a three to fourfold molar excess of reagent was used at pH 9.0–10.0. Excess reagent was extracted with n-hexane–ethyl acetate 9:1–10:1 (v/v); this enabled direct analysis using CE with no significant disturbance from the major fluorescent reagent degradation by-products. The effects on the results of buffer pH and of SDS and organic modifier concentrations were examined. Good baseline resolution in the separation of five CEOC-peptides was achieved with a 48.5-cm total length (effective length 40 cm) 50-μm inner diameter capillary column.  相似文献   

11.
The fifteen intermetallic compounds R4Pd9Al24 (R = Gd–Tm) and R4Pt9Al24 (R = Y, Gd–Lu) were prepared by reaction of the elemental components. Their crystal structure was determined from single-crystal X-ray data of Er4Pt9Al24. It is pseudo-trigonal with triclinic symmetry: P 1, a = b = 747.5(2) pm, c = 1306.7(4) pm, α = 100.99(2)°, β = 95.47(2)°, γ = 60.00(3)°, Z = 1, R = 0.052 for 2593 structure factors and 110 variable parameters. The structure is closely related to that of Y2Co3Ga9. Both may be described as stacking variants of each other. They consist of layers of the compositions PtAl2 (CoGa2), and Er2Al3 (Y2Ga3), designated A and B, respectively. These layers are stacked in the five- and four-layer sequences ABAAB (Er4Pt9Al24) and ABAB (Y2Co3Ga9). The layers PtAl2 and CoGa2 are similar to the hexagonal close packed layers in the TiSi2-, CrSi2-, and MoSi2-type structures. The structure of Er4Pt9Al24 contains a monoclinic subcell, where the layers Er2Al3 are disordered. A partial disorder of this kind, which could be ascribed to twinning or to the intergrowth with another stacking variant, was found during the structure refinement of the isotypic compound Y4Pt9Al24: a = b = 749.0(2) pm. c = 1309.3(4) pm, α = 100.99(2)°, β = 95.48(2)°, γ = 60.00(3)°, R = 0.031 for 1435 structure factors and 128 variable parameters.  相似文献   

12.
《中国化学》2017,35(12):1869-1874
A metal‐organic framework (MOF ) formulated as [Cd23‐L)2(DMF )4]•H2O ( CdL ) [H2L =9‐(pyridin‐4‐yl)‐ 9H ‐carbazole‐3,6‐dicarboxylic acid, DMF =N ,N ‐dimethylformamide] was synthesized under solvothermal condition. Crystal structural analysis reveals that CdL features the layered 2D framework with L2 ligands as 3‐connected nodes. The compound CdL emits blue‐violet light with the narrow emission peak and the emission maximum at 414 nm upon excitation at the maximum excitation wavelength of 340 nm. The compound CdL has a similar emission spectrum curve to the free H2L ligand that indicates the emission of compound CdL should be originated from the coordinated L2 ligands.  相似文献   

13.
Summary 1-(Dipyrrinon-9-yl)-3-(dipyrrinon-9-ylidene)-propene, ab-vinylogous verdin, was synthesized by condensation of 3-(dipyrrinon-9-yl)-propenal with a dipyrrinone unsubstituted in position 9. By condensing the latter with dimedone or squaric acid,b-vinylogous verdin pigments with restricted configurational and conformational degrees of freedom were obtained. The chemical and spectroscopic properties of these novel systems are discussed.
Zur Chemie von Pyrrolpigmenten, 94. Mitt.: 1-(Dipyrrinon-9-yl)-3-(dipyrrinon-9-yliden)-1-propen — Ein neuerb-vinyloger Verdinchromophor
Zusammenfassung 1-(Dipyrrinon-9-yl)-3-(dipyrrinon-9-yliden)-propen, einb-vinyloges Verdin, wurde durch Kondensation von 3-(Dipyrrinon-9-yl)-propenal mit einem in Position 9 unsubstituierten Dipyrrinon dargestellt. Kondensation des Letzteren mit Dimedon oder Quadratsäure lieferte vinyloge Pigmente, welche in ihren konfigurationellen und konformationellen Freiheiten eingeschränkt sind. Die chemischen und spektroskopischen Eigenschaften dieser neuen Systeme werden diskutiert.
  相似文献   

14.
Drim-9(11)-en-8α-ol and drim-9(11)-en-8β-ol were synthesized in six steps from drimenol. Drimenol was oxidized by P2O5 and DMSO to drimenal, which isomerized with p-TsOH into isodrimenal. Isodrimenal was reduced by NaBH4 into isodrimenol, epoxidation of which by m-CPBA gave a mixture (3.4:1) of α- and β-epoxyisodrimenols. These reacted with tosyl chloride in Py to give a mixture of α- and β-epoxyisodrimenol tosylates. Treatment of the tosylate mixture with KI and then Ph3P produced a mixture of drim-9(11)-en-8α- and -8β-ols that was separated chromatographically. The overall yield was ∼26%.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 152–155, March–April, 2005.  相似文献   

15.
合成了3个有机锡9-芴酮-4-甲酸酯:三苯基锡9-芴酮-4-甲酸酯[(C6H5)3Sn(C14H7O3)](1)、三环己基锡9-芴酮-4-甲酸酯[(C6H11)3Sn(C14H7O3)](2)和三(2-甲基-2-苯基丙基)锡9-芴酮-4-甲酸酯[(C6H5C(CH3)2CH2)3Sn(C14H7O3)](3)。通过元素分析、红外光谱、核磁共振谱(1H、13C和119Sn)、热重分析进行了表征;用单晶X射线衍射方法测定了化合物的晶体结构,并对其进行了量子化学计算和体外抗...  相似文献   

16.
A dicarboxylic acid ( I ) was prepared from the condensation of 9,9-bis[4-(4-aminophenoxy) phenyl] fluorene and trimellitic anhydride. A new family of poly(amide-imide)s having inherent viscosities of 0.75-1.04 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid I with various aromatic diamines in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 262–325°C and the 10% weight loss temperatures were above 525°C in air. © 1994 John Wiley & Sons, Inc.  相似文献   

17.
Four new chiral triorganotin(IV) carboxylates, [(R3Sn)(O2C13H17)] n (R?=?Me 1, Ph 2), [(R3Sn)(O2C13H17)] (R?=?n-Bu 3), and [(R3Sn)(O4C9H9)] n (R?=?Me 4), have been synthesized by reaction of (S)-(+)-2-(4-isobutyl-phenyl)propionic acid and (R)-(+)-2-(4hydroxyphenoxy)propionic acid with triorganotin(IV) chloride in the presence of sodium ethoxide. The complexes have been characterized by elemental analyses, FT-IR, NMR (1H, 13C, and 119Sn) spectra, and X-ray crystallography diffraction analyses. Structural analyses show that 1 has a 1-D infinite chiral zigzag chain structure. Complexes 2 and 4 have a 1-D spring-like chiral helical chain with a channel, while 3 is a monomer. Antitumor activities of 14 have been studied.  相似文献   

18.
Jing Cao  Yang Li  Junxiang Feng 《中国化学》2012,30(7):1571-1574
Two kinds of novel styryl chemosensory 2‐FMNC and 3‐FMNC, were designed and synthesized by an apporiate introduction of 9‐benzylidene‐9H‐fluorene group as fluorophore with the aim at avoiding photoisomerisation. These 9‐benzylidene‐9H‐fluorene derivatives showed the similar selectivity and sensitivity upon addition of metal ions. The sensitivity of FMNC to alkaline earth metal ions was Ba2+>Sr2+>Ca2+≈Mg2+.  相似文献   

19.
以4-(2-(4-咪唑)苯乙烯基)吡啶(ISPE)为配体,分别与间苯二甲酸(1,3-H_2BDC)、4,4′-联苯二甲酸(4,4′-H_2BPDC)和4,4′-二苯乙烯二甲酸(4,4′-H_2STDC)及过渡金属盐Cd(NO3)2·4H_2O通过溶剂热自组装形成了3种配位聚合物晶体{[Cd_2(ISPE)_2(1,3-BDC)_2]·DMF}_n(1)、[Cd(ISPE)(4,4′-BPDC)]_n(2)和[Cd(ISPE)_2(4,4′-STDC)(H_2O)_2]_n(3)。并用单晶X射线衍射、PXRD、红外光谱、元素分析、热重等对其进行了表征。单晶解析结果表明:配位聚合物1是二维层状网格结构,配位聚合物2是一个六重穿插的类金刚烷三维网格结构,配位聚合物3是由一维网格结构通过氢键和分子间作用力堆积形成的三维网格结构。另外还研究了它们的室温固态荧光性能。  相似文献   

20.
Summary By condensing a dipyrrinon-9-yl-acrolein with a dipyrrinone unsubstituted in position 9, an unsymmetricb-vinylogous verdinoid pigment was prepared. The configuration of this molecule was elucidated by means of 2D1H NMR experiments to be (4Z,10E,12Z,17Z) in solutions of chloroform and dimethylsulfoxide, and its conformation was derived to be 5syn,9syn,11anti,16syn. The pronounced solvatochromic effect of this molecule with a cyclic helical geometry could be explained by solvent induced conformational changes.
Zur Chemie von Pyrrolpigmenten, 97. Mitt.: Synthese, Stereochemie und Solvatochromer Effekt eines 1-(Dipyrrinon-9-yl)-3-(dipyrrinon-9-yliden)-1-propens
Zusammenfassung Durch Kondensation eines Dipyrrinon-9-yl-acroleins mit einem in Position 9 unsubstituierten Dipyrrinon wurde ein unsymmetrischesb-vinyloges verdinoides Pigment dargestellt. Die Konfiguration dieses Moleküls wurde mit Hilfe von 2D-1H-NMR-Experimenten in Lösungen von und Dimethylsulfoxid als (4Z,10E,12Z,17Z) abgeleitet; seine Konformation konnte zu 5syn,9syn,11anti,16syn festgelegt werden. Die ausgeprägte Solvatochromie dieses Moleküls mit cyclisch helikaler Geometrie konnte auf solvensinduzierte konformative Veränderungen zurückgeführt werden.
  相似文献   

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