2-（4-Decarboxydehydroabietyl）-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the ort...2-（4-Decarboxydehydroabietyl）-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the orthorhombic system, space group P212121 with a = 6.1351（5）, b = 14.8495（19）, c = 25.9050（2） A, V = 2360.0（4） A3, Z = 4, Mr = 414.57, Dc = 1.167 Mg/m^3, 2 = 0.71073 A,μ（MoKa） = 0.070 mm^-1, F（000） = 896, the final R = 0.0452 and wR = 0.1076 for 1647 observed reflections with I 〉 2σ（I）. There are five rings in the crystal structure of the title compound, but the oxadiazole ring is non-coplanar with the benzene ring D.展开更多
A novel sulfur-promoted cyclization of hydrazides and isonitriles to produce 1,3,4-oxadiazole has been devel- oped. The method is operationally simple and compatible with a wide scope of substrates and various 2-amino...A novel sulfur-promoted cyclization of hydrazides and isonitriles to produce 1,3,4-oxadiazole has been devel- oped. The method is operationally simple and compatible with a wide scope of substrates and various 2-amino- 1,3,4-oxadiazoles are efficiently obtained in good yields.展开更多
A new conjugated copolymer （PTST-DyOXD） derived from 1,1-dimethyl-3,4-diphenyl-2,5-bis（5-bromo-2- thienyl）-silole （TST） and 2,5-bis（4-ethynylphenyl）-l,3,4-oxadiazole （DyOXD） was synthesized by Pd（0）-cataly...A new conjugated copolymer （PTST-DyOXD） derived from 1,1-dimethyl-3,4-diphenyl-2,5-bis（5-bromo-2- thienyl）-silole （TST） and 2,5-bis（4-ethynylphenyl）-l,3,4-oxadiazole （DyOXD） was synthesized by Pd（0）-catalyzed Sonogashira coupling reaction. For comparison, another copolymer without acetenyl group （PTST-OXD） was also synthesized by Pd（0）-catalyzed Suzuki coupling reaction. Chemical structures and optoelectronic properties of the copolymers were characterized by IH NMR, 13C NMR, IR, UV-vis absorption, photoluminescence and cyclic voltammetry. The number-average molecular weight （Mn） is 4010 Da for PTST-DyOXD and 3890 Da for PTST-OXD, respectively. The thermogravimetric analysis （TGA） measurements show that they have good thermal stability with decomposition temperature at 312 and 318 ~C, respectively. The optical band gap is 2.21 eV for PTST-DyOXD and 2.10 eV for PTST-OXD based on the absorption onset. CV analysis revealed the LUMO level of PTST-DyOXD is -3.04 eV, lower than that of PTST-OXD （about -2.89 eV）, which is attributed to the introduction of acetylene group in PTST-DyOXD, increasing the system of the conjugate chain length.展开更多
基金Supported by the Foundation of 100 Young and Middle-aged Discipline Leaders of Guangxi Province in the 21st century (No. 2004219)the Natural Science Foundation of Guangxi Province (No. 0731054)
文摘2-（4-Decarboxydehydroabietyl）-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the orthorhombic system, space group P212121 with a = 6.1351（5）, b = 14.8495（19）, c = 25.9050（2） A, V = 2360.0（4） A3, Z = 4, Mr = 414.57, Dc = 1.167 Mg/m^3, 2 = 0.71073 A,μ（MoKa） = 0.070 mm^-1, F（000） = 896, the final R = 0.0452 and wR = 0.1076 for 1647 observed reflections with I 〉 2σ（I）. There are five rings in the crystal structure of the title compound, but the oxadiazole ring is non-coplanar with the benzene ring D.
文摘A novel sulfur-promoted cyclization of hydrazides and isonitriles to produce 1,3,4-oxadiazole has been devel- oped. The method is operationally simple and compatible with a wide scope of substrates and various 2-amino- 1,3,4-oxadiazoles are efficiently obtained in good yields.
基金The authors are grateful to financial support from the National Natural Science Foundation of China，the East China University of Science and Technology
文摘A new conjugated copolymer （PTST-DyOXD） derived from 1,1-dimethyl-3,4-diphenyl-2,5-bis（5-bromo-2- thienyl）-silole （TST） and 2,5-bis（4-ethynylphenyl）-l,3,4-oxadiazole （DyOXD） was synthesized by Pd（0）-catalyzed Sonogashira coupling reaction. For comparison, another copolymer without acetenyl group （PTST-OXD） was also synthesized by Pd（0）-catalyzed Suzuki coupling reaction. Chemical structures and optoelectronic properties of the copolymers were characterized by IH NMR, 13C NMR, IR, UV-vis absorption, photoluminescence and cyclic voltammetry. The number-average molecular weight （Mn） is 4010 Da for PTST-DyOXD and 3890 Da for PTST-OXD, respectively. The thermogravimetric analysis （TGA） measurements show that they have good thermal stability with decomposition temperature at 312 and 318 ~C, respectively. The optical band gap is 2.21 eV for PTST-DyOXD and 2.10 eV for PTST-OXD based on the absorption onset. CV analysis revealed the LUMO level of PTST-DyOXD is -3.04 eV, lower than that of PTST-OXD （about -2.89 eV）, which is attributed to the introduction of acetylene group in PTST-DyOXD, increasing the system of the conjugate chain length.
