Use of free air as oxidant and copper(II)chloride as catalyst,3,3'-di-tert-butylbi-phenyl-2,5,2',5'-diquinone(BBDQ)was prepared via catalytic oxidation of 2,2'-dihydroxy-3,3'-di-tert-butyl-5,5'-dimethoxy-bip...Use of free air as oxidant and copper(II)chloride as catalyst,3,3'-di-tert-butylbi-phenyl-2,5,2',5'-diquinone(BBDQ)was prepared via catalytic oxidation of 2,2'-dihydroxy-3,3'-di-tert-butyl-5,5'-dimethoxy-biphenyl(di-BHA).The yield of reaction attained 95% and the selectivity for BBDQ was 100%.The single-crystal X-ray diffraction analysis reveals that the dihedral angle between two rings(benzene rings for di-BHA and quinone rings for BBDQ)changes from 89.8 to 45.3o,indicating the steric hindrance effects of methyl disappear in the oxidation process.The crystal structures of di-BHA and BBDQ are further confirmed by their spectral characterizations.The probable mechanism for this oxidation process is also discussed.展开更多
2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl ...2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl chloride catalysts the reaction is limited to give only 1,8-dioxo-octahydroxanthenes 3a-k in very good yields.展开更多
A series of new complex salts of the type [R]2[MC14] where R =[Ph-C=n-N-Ph N=N-Ph],M = Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ wereprepared and characterized by elemental analysis, molar conductance, IR and UVNis is spec...A series of new complex salts of the type [R]2[MC14] where R =[Ph-C=n-N-Ph N=N-Ph],M = Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ wereprepared and characterized by elemental analysis, molar conductance, IR and UVNis is spectral studies and magnetic measurements.The crystal structure of[Ph-C=n-N-Ph N=N-Ph]2[CuCl4] was determined by single crystal X-ray crystallography. The structure consisted of anion part and a 2,3,5-(triphenyl) tetrazolium cation as counter ions. The copper complex has a distorted tetrahedral geometry, the CI(1)-Cu-CI(2) [124.33 (2°)] and Cl(3)-Cu-Cl(4) [131.03 (2°)] angles are significantly larger than the ideal tetrahedral. The [CuCI4] anion and its counter ions are connected through a hydrogen bonds between C1 of the dianion and hetero aromatic rings by Cl-π, π-π and C-H … π, interactions.展开更多
目的研究抗生素氟氯西林钠的关键中间体3-(2′-氯-6′-氟苯基)-5-甲基-4-异噁唑甲酰氯的合成方法,使之适合工业化生产。方法以2-氯-6-氟苯甲醛为原料,经肟化、氯化、环合、水解、酰氯化等步骤制得目标化合物。结果合成产物的化学结构经I...目的研究抗生素氟氯西林钠的关键中间体3-(2′-氯-6′-氟苯基)-5-甲基-4-异噁唑甲酰氯的合成方法,使之适合工业化生产。方法以2-氯-6-氟苯甲醛为原料,经肟化、氯化、环合、水解、酰氯化等步骤制得目标化合物。结果合成产物的化学结构经IR,1H-NMR,13C-NMR and MS确证,总收率为60.2%。结论此方法收率高,成本低,适合工业化生产。展开更多
基金supported by the 973 Program (2005CB623607)the National Natural Science Foundation of China (No.20771061)the scientific program 2008BAE64B09
文摘Use of free air as oxidant and copper(II)chloride as catalyst,3,3'-di-tert-butylbi-phenyl-2,5,2',5'-diquinone(BBDQ)was prepared via catalytic oxidation of 2,2'-dihydroxy-3,3'-di-tert-butyl-5,5'-dimethoxy-biphenyl(di-BHA).The yield of reaction attained 95% and the selectivity for BBDQ was 100%.The single-crystal X-ray diffraction analysis reveals that the dihedral angle between two rings(benzene rings for di-BHA and quinone rings for BBDQ)changes from 89.8 to 45.3o,indicating the steric hindrance effects of methyl disappear in the oxidation process.The crystal structures of di-BHA and BBDQ are further confirmed by their spectral characterizations.The probable mechanism for this oxidation process is also discussed.
基金support from the Research Council of University of Sistan and Baluchestan, Iran
文摘2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) 4l-s produced from reaction between dimedone with various aldehydes in acetonitrile using ZnO as a catalyst;whereas in the presence of ZnO-acetyl chloride catalysts the reaction is limited to give only 1,8-dioxo-octahydroxanthenes 3a-k in very good yields.
文摘A series of new complex salts of the type [R]2[MC14] where R =[Ph-C=n-N-Ph N=N-Ph],M = Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ wereprepared and characterized by elemental analysis, molar conductance, IR and UVNis is spectral studies and magnetic measurements.The crystal structure of[Ph-C=n-N-Ph N=N-Ph]2[CuCl4] was determined by single crystal X-ray crystallography. The structure consisted of anion part and a 2,3,5-(triphenyl) tetrazolium cation as counter ions. The copper complex has a distorted tetrahedral geometry, the CI(1)-Cu-CI(2) [124.33 (2°)] and Cl(3)-Cu-Cl(4) [131.03 (2°)] angles are significantly larger than the ideal tetrahedral. The [CuCI4] anion and its counter ions are connected through a hydrogen bonds between C1 of the dianion and hetero aromatic rings by Cl-π, π-π and C-H … π, interactions.
文摘目的研究抗生素氟氯西林钠的关键中间体3-(2′-氯-6′-氟苯基)-5-甲基-4-异噁唑甲酰氯的合成方法,使之适合工业化生产。方法以2-氯-6-氟苯甲醛为原料,经肟化、氯化、环合、水解、酰氯化等步骤制得目标化合物。结果合成产物的化学结构经IR,1H-NMR,13C-NMR and MS确证,总收率为60.2%。结论此方法收率高,成本低,适合工业化生产。