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二代螺环树形化合物1,2,3,4,5,6,7,8,9,10,11,12-十二氢-2,2;6,6;10,10-三[3,3-二(烷氧羰基)-1,1-环亚丁基二甲氧基]三亚苯基的合成  [PDF]
化学学报 , 2007,
Abstract: 以1,4-环己二酮、丙二酸二乙酯及多元醇等为原料,经过两次“一锅煮”法合成了六种二代螺环树形化合物1,2,3,4,5,6,7,8,9,10,11,12-十二氢-2,2;6,6;10,10-三[3,3-二(烷氧羰基)-1,1-环亚丁基二甲氧基]三亚苯基螺环树形化合物,其中烷氧基为异戊氧基、三羟甲基甲氧基、2,2-二溴甲基-3-羟丙氧基、2,2-二羟甲基丙氧基、二羟甲基膦甲氧基和(N-羟甲基-N-二羟甲基氨基乙基)甲氧基.利用IR,NMR,MS和元素分析对合成的化合物进行了结构认证,对影响反应的因素进行了讨论.
7,7′,8,8′-Tetramethoxy-4,4′-dimethyl-3,3′-bicoumarin  [cached]
Hoong-Kun Fun,Samuel Robinson Jebas,Mehtab Parveen,Zakia Khanam
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809017334
Abstract: In the crystal structure, the title compound, C24H22O8, lies on a twofold rotation axis and the asymmetric unit comprises one half-molecule. The dihedral angle formed by the coumarin unit with the symmetry-related part is 74.78 (14)°. One of the methoxy groups attached to the coumarin unit is considerably twisted, making an angle of 87.17 (17)° with respect to the coumarin unit; the other is twisted by 0.66 (19)°. No classical hydrogen bonds are found in the sturcture; only a weak C—H...π interaction and short intramolecular O...O contacts [2.683 (2)–2.701 (2) ] are observed.
Synthesis and Crystal Structure Determination of 4’,9’,4”,9”-Tetra-t-Butyl- 1’,6’,1”,6”-Tetramethoxy-2,5-Dithia[3.3] Metabiphenylophane  [PDF]
Tetsuji Moriguchi, Tatsuya Egami, Daisuke Yakeya, Venkataprasad Jalli, Kenji Yoza, Akihiko Tsuge
Crystal Structure Theory and Applications (CSTA) , 2016, DOI: 10.4236/csta.2016.53005
Abstract: The title compound 4’,9’,4”,9”-tetra-tert-butyl-1’,6’,1”,6”-tetramethoxy-2,5-dithia[3.3] metabiphenylophane was synthesized as a calixarene like large-sized metacyclophane from the corresponding 3,3’-bis(chloromethyl)-5,5’-bis(1,1-dimethylethyl)-2,2’-dimethoxy-1,1’-biphenyl and 3,3’-bis (mercaptomethyl)-5,5’-bis(1,1-dimethylethyl)-2,2’-dimethoxy-1,1’-biphenyl via an intermolecular condensation reaction. The compound was characterized using 1H NMR spectroscopy and mass spectrometry. Its exact conformational structure was determined via single crystal X-ray diffraction analysis. The compound has quite strained 1,2-alternate like structure because of its two high dihedral angled and rigid biphenyl parts in the crystal. The crystal includes the two isomers as two different 1,2-alternate like conformers, and the ratio of the two isomers is 78:22.
7,7′,8,8′-Tetramethoxy-4,4′-dimethyl-3,5′-bichromene-2,2′-dione  [cached]
Hoong-Kun Fun,Samuel Robinson Jebas,Mehtab Parveen,Zakia Khanam
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809018029
Abstract: In the title molecule, C24H22O8, the mean planes of the two coumarin units are inclined to each other at a dihedral angle of 79.93 (3)°. The attached methoxy groups form torsion angles of 7.65 (19) and 78.36 (14)° with respect to one coumarin unit, and angles of 9.01 (16) and 99.08 (11)° with respect to the other coumarin unit. In the crystal structure, weak intermolecular C—H...O hydrogen bonds connect pairs of molecules to form dimers, generating R22(16) and R22(18) rings; the dimers are linked by further weak intermolecular C—H...O hydrogen bonds, forming extended chains. Additional stabilization is provided by weak C—H...π interactions.
Nanomechanical Properties and Phase Transitions in a Double-Walled (5,5)@(10,10) Carbon Nanotube: ab initio Calculations  [PDF]
A. M. Popov,Yu. E. Lozovik,A. S. Sobennikov,A. A. Knizhnik
Physics , 2009, DOI: 10.1134/S1063776109040104
Abstract: The structure and elastic properties of (5,5) and (10,10) nanotubes, as well as barriers for relative rotation of the walls and their relative sliding along the axis in a double-walled (5,5)@(10,10) carbon nanotube, are calculated using the density functional method. The results of these calculations are the basis for estimating the following physical quantities: shear strengths and diffusion coefficients for relative sliding along the axis and rotation of the walls, as well as frequencies of relative rotational and translational oscillations of the walls. The commensurability-incommensurability phase transition is analyzed. The length of the incommensurability defect is estimated on the basis of ab initio calculations. It is proposed that (5,5)@(10,10) double-walled carbon nanotube be used as a plain bearing. The possibility of experimental verification of the results is discussed.
4He adsorbed inside (10,10) single walled carbon nanotubes  [PDF]
M. C. Gordillo,J. Boronat,J. Casulleras
Physics , 2007, DOI: 10.1103/PhysRevB.76.193402
Abstract: Diffusion Monte Carlo calculations on the adsorption of $^4$He in open-ended single walled (10,10) nanotubes are presented. We have found a first order phase transition separating a low density liquid phase in which all $^4$He atoms are adsorbed close to the tube wall and a high density arrangement characterized by two helium concentric layers. The energy correction due to the presence of neighboring tubes in a bundle has also been calculated, finding it negligible in the density range considered.
10,10-二吡啶甲基-9,10-二氢蒽的合成研究有机化学  [PDF]
张红, 刘文杰, 曹德榕, 江焕峰
有机化学 , 2011,
Abstract: 蒽酮1和氯甲基吡啶盐酸盐2在甲苯中回流反应生成10,10-二吡啶甲基-9(10H)蒽酮(3),收率63%~68%|3用硼氢化钠还原生成10,10-二吡啶甲基-9,10-二氢蒽-9-醇(4),收率87%~90%|蒽醇4在酸催化下发生歧化反应,得到还原产物10,10-二吡啶甲基-9,10-二氢蒽(5)和氧化产物蒽酮3.该歧化反应受催化剂、溶剂和反应温度等影响.当蒽醇4用三氟化硼为催化剂、甲苯为溶剂、回流反应,5的收率达到74%.所合成的新化合物都经1HNMR,13CNMR,MS和元素分析表征确认.
Boletín de la Sociedad Chilena de Química , 2000,
Abstract: Synthesis and spectroscopical characterization of 3,3'''-dioctyltetrathiopheneoligomer has been carried out. The dioctyl tetrathiophene was preparedby the nickel catalyzed cross-coupling reaction starting from 3,3'-diocytilbithiopheneand 2-bromo-octylthiophene. The spectroscopical properties are reported.(UV, FT-IR, 1H-NMR, 13C-NMR) Se ha realizado la síntesis y caracterización espectroscópicadel 3,3'''-dioctiltetratiofeno. El tetrámero se preparó utilizandola reacción de acoplamiento entre el 3,3'-dioctilbitiofeno y el2-bromo-3-octiltiofeno catalizada por níquel. Las propiedades espectroscópicasde UV, FT-IR, 1H-NMR, 13C-NMR son reportados
Boletín de la Sociedad Chilena de Química , 2000, DOI: 10.4067/S0366-16442000000100008
Abstract: synthesis and spectroscopical characterization of 3,3'''-dioctyltetrathiopheneoligomer has been carried out. the dioctyl tetrathiophene was preparedby the nickel catalyzed cross-coupling reaction starting from 3,3'-diocytilbithiopheneand 2-bromo-octylthiophene. the spectroscopical properties are reported.(uv, ft-ir, 1h-nmr, 13c-nmr)
On (3,3)-homogeneous Greechie Orthomodular Posets  [PDF]
Foat F. Sultanbekov
Mathematics , 2002,
Abstract: We describe a (3,3)-homogeneous orthomodular posets for some cardinality of their sets of atoms. We examine a state space and a set of two-valued states of such logics. Particular homogeneous OMPs with exactly k pure states (k=1,...,7, 10,11)
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