Optical properties of a polydiacetylene crystal: poly-[1,6-di(N-carbazolyl)-2,4-hexadiyne]

Normal incidence reflection spectra and Kramers-Kronig transforms are reported for a polydiacetylene crystal, DCHD (substituent group: N-carbazolymethyl). The lowest energy optical transition for the polymer backbone is found at 15 300 cm^?1, the lowest value obtained thus far for a polydiacetylene. The polymer chain and the carbazolyl substituent group may be treated as isolated chromophores - the former dominating the visible portion of the spectra and the latter dominating the UV portion. Polarization studies for the (001) and (10$\text{1}\text{?}$) faces of DCHD permit unambiguous assignment of the two lowest energy transitions in the carbazolyl group at 28 750 cm^?1 and 33 250 cm^?1 as short- and long-axis polarized, respectively.     

Synthesis of 7-(3-piperidyl)-[1,6]naphthyridine and 7-(4-pipe-ridyl)[1,6]naphthyridine

7-(3-Piperidyl)- and 7-(4-piperidyl)[1,6]naphthyridines have been synthesized from 2-methylpyridine-3-carbaldehyde cyclohexylimine and the methylmethoxycarboxamides (Weinreb amides) of N-Boc- substituted nipecotic and isonipecotic acids.     

Synthesis of 3-acylmethyl-1,5-dihydrobenzo[e]-2,4-dithiepins and 1,2-di(acylvinylthiomethyl)-4,5-dimethylbenzenes from α-acetylene ketones

Substituted 1,5-dihydrobenzo[e]-2,4-dithiepins and 1,2-di(acylvinylthiomethyl)-4,5-dimethylbenzenes were synthesized by the reaction between -acetylene ketones and 1,2-dimethyl-4,5-di(mercaptomethyl)benzene in chloroform in the presence of K₂CO₃ or in methanol in the presence of triethylamine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 203–205, February, 1985.     

Synthesis, chemical properties and mutagenicity of 1,6- and 3,6-dinitrobenzo[a]pyrenes

Nitration of benzo[a]pyrene (BaP) with HNO3 (d = 1.38) produced a mixture of dinitroBaPs (1,6- and 3,6-isomers) and mononitroBaPs (1-, 3- and 6-isomers). Pure 1,6-dinitroBaP and 3,6-dinitroBaP were obtained by the reduction of the dinitroBaPs mixture with NaSH to yield the separable products 1-amino-6-nitroBaP and 3-amino-6-nitroBaP, followed by conversion to dinitroBaPs via the the diazonium salts. The half-wave potentials (E1/2) corresponding to the one-electron reduction of dinitroBaPs were measured and the relationship of these values to the mutagenicity is discussed.     

Synthesis and properties of 1,6-dioxaspiro[4.4]nonane and its derivatives (review)

Data on methods of synthesis and the chemical properties of 1,6-dioxaspiro-[4.4]nonane and its derivatives are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1155–1168, September, 1986.     

四羰基双[2,5-二(三甲硅基)-1-甲基环戊二烯基]

由甲基环戊二烯经两步类似反应向其环上引入两个Me3Si取代基, 生成(Me3Si)2-MeC5H3, 后者与Fe(CO)5反应除生成预期的双核Fe-Fe键产物[η^5-{Me3Si)2MeC5H2}Fe(CO)]2-(μ-CO)2(2)外, 还分离到小量单核化合物η^5-[(Me2Si)2MeC5H2]Fe(CO)2Cl(3), 2与碘反应生成Fe-Fe键断裂的单核铁碘化物(4)。2经Na/Hg还原生成Fe-Fe键断裂的铁负离子, 后者随即分别与数种氯化物反应, 生成在铁原子上引入相应取代基的铁衍生物η^5-[(Me3Si)2MeC5H2]Fe(CO)2R(R=PhCH2, 5; CH2COOC2H5, 6; Ph3Sn, 7; Ph2SnCl, 8)。测定了4的晶体结构, 晶体属单斜晶系, P21/c空间群, 晶胞参数a=0.7333(1), b=2.0089(3),c=1.3323(4)nm; β=92.02(2)°, V=1.962(1)nm^3, Z=4。     

3-[N-(4-甲基苯基)氨基羰基]-5-[4-(4-甲酸基苯甲氧基)苯亚甲基]-2,4-噻唑烷二酮的合成

以对甲苯胺和对甲基苯甲酸甲酯为起始原料,经NBS溴化、亲核取代、酸水解和Knoevenagel缩合等6步反应合成了抗细菌生物膜化合物—3-[N-(4-甲基苯基)氨基羰基]-5-[4-(4-甲酸基苯甲氧基)苯亚甲基]-2,4-噻唑烷二酮,总收率57.3％,其结构经1H NMR,ESI-MS和元素分析确证.     

Synthesis and characterization of new polyamides derived from 1,6-bis[4-(4-aminophenoxy)phenyl]diamantane

A series of new polyamides 3 were synthesized by direct polycondensation of the 1,6-bis[4-(4-aminophenoxy)phenyl]diamantane (1) with various dicarboxylic acids. The polyamides had inherent viscosities of 0.45–1.90 dL/g and number-average molecular weights (M_n) of 24,000–110,000. Dynamic mechanical analysis (DMA) reveals that polymers 3 have two relaxations on the temperature scale between −100 and 400°C. Their α relaxations occurred at high temperatures, ranging from 338 to 389°C. Moreover, these polymers remained quite stable at high temperatures and maintained good mechanical properties (G′ = ca. 10⁸ Pa) up to temperatures close to the main transition markedly exceeding 350°C. Due to the bulky diamantane elements and the flexible ether segments, the polymers 3 were amorphous and soluble in a number of organic solvents such as pyridine, N-methyl-2-pyrrolidone (NMP), and N,N-dimethylacetamide (DMAc). The polyamides 3 have tensile strengths of 56.7–90.2 MPa, elongation to breakage values of 7.5–27.7%, and initial moduli of 1.8–2.1 GPa. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2185–2192, 1998     

1,6:9,14-bismethano[16]annulene - a new bridged [4n]annulene

The molecular structure and dynamic behaviour of the bridged [4n] annulene 1,6:9,14-bismethano-[16]annulene is unravelled by NMR and X-ray investigations, combined with force field calculations.     

Spectroscopic studies of solutions,suspensions, and precipitates of poly(1,6-di-p-toluene sulfonyloxy-2,4-hexadiyne)

Optical-absorption, fluorescence, and Raman spectra for solutions, suspensions, and precipitates of poly(1,6-di-p-toluene sulfonoxy-2,4-hexadiyne) in and from nitrobenzene, acetone, and chloroform are presented. These are interpreted in terms of the occurrence of two forms of the polymer chain; a quasicrystalline form with properties close to those of single crystal polymer and a chain-extended form occurring in solution and colloidal particles, with an absorption energy of about 2.5 eV (20,000 cm^?1). No evidence is found for the presence of very short polymer chains in partially polymerized monomer at low conversion. The relationship of these results to those for deformed single crystals is briefly discussed.     

Synthesis and Crystal Structure of 3,3-Dimethyl-7,11-di（thiophene- 2-yl）-2,4-dioxyspiro[5. 5]undecane- 1,5,9-trione

The title compound （C19H18O5S2） has been synthesized by the reaction of thio- phene-2-carboxaldehyde, isopropylidene malonate and 4-chloroaniline using [bmim]Br as solvent, and characterized by IR, ^1H NMR and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n with a = 9.4872（15）, b = 9.5148（13）, c = 20.634（3）A, β= 92.209（2）°, V= 1861.2（4）A^3, Mr= 390.45, Z = 4, Dc = 1.393 g/cm^3,μ（MoKα） = 0.313 mm^-1, F（000） = 816, the final R = 0.0685 and wR = 0.1685. X-ray analysis reveals that two six-membered rings adopt chair and planar conformations, respectively.     

The mass spectral rearrangements of 1,6-bis(arylsulfenyl)-2,4-hexadiynes and 1,6-bis(arylsulfonyl)-2,4-hexadiynes

The mass spectral. behavior of 1,6-bis(arylsulfenyl)-2,4-hexadiynes and 1,6-bis(arylsulfonyl)-2,4-hexadiynes were examined. The sulfenyl derivatives extruded the hexadiynyl moiety with the formation of Ar? S? S? Ar fragments. The sulfonyl derivatives, on the other hand, showed no extrusion of the hexadiyne fragment but an expulsion of SO₂ and even two SO₂ units.     

1,3-di(methythio)-2,2,4,4-tetramethylbicyclo[1.1.0]butane

1,3-Di(methylthio)-2,2,4,4-tetramethylbicyclo[1.1.0]butane has been synthesized by two alternate routes and has been characterized by single crystal X-ray crystallography. This report corrects earlier, erroneous discussions of the title compound which have appeared in the literature.     

Synthesis of some new pyrimido[1,6-a]pyrimidines

4-Amino-5-arylpyrimidines 1 react with diethyl alkylmalonates 2 to give pyrimido[1,6-a]pyrimidines 4 in satisfactory yields. A possible mechanistic scheme and the spectral data of the reaction products are discussed.     

Synthesis and properties of [1,6′]biazulenyl compounds

The synthesis of a new biazulenyl system, which contains azulene moieties coupled in 1- and 6-position is reported. The structure of the isolated compounds, as well as the calculated dihedral angle between the planes of the coupled moieties, has been correlated with the recorded spectra.