In the presence of equimolar triethylamine,vicinal dibromides were found to be easily debrominated by dibutyl telluride,forming the co- rresponding olefins.
The fragmentation patterns of a series of dispirocyclopiperazinium dibromides with strong analgesic activity during positive ion electrospray ionization mass spectrometry were analyzed. The [M-Br]^＋ 2 ions showed the...The fragmentation patterns of a series of dispirocyclopiperazinium dibromides with strong analgesic activity during positive ion electrospray ionization mass spectrometry were analyzed. The [M-Br]^＋ 2 ions showed the characteristic isotopic peaks and were assigned as the molecular ions. The loss of a 44 Dalton unit from 2 produced ion 3 [M-Br-44]^＋ and the loss of HBr from 2 formed ion 4. Besides, the carbamates 1d-1e produced extra ions [M-2Br-33]^＋. The related fragmentation mechanisms were proposed.展开更多
The ? ?vicinal dibromo carboxylic acid and its derivatives were debrominated with Sm/HOAc system to afford the corresponding cinnamic acid and its derivatives in good yields under mild conditions.
The C/PbO2 electrode assisted electrochemical removal of diquat dibromide herbicides solutions has been the subject of the present investigation under several operating conditions. The optimum conditions of the treatm...The C/PbO2 electrode assisted electrochemical removal of diquat dibromide herbicides solutions has been the subject of the present investigation under several operating conditions. The optimum conditions of the treatment process are: current density of 150 mA/cm2, pH 2.2, NaCl concentration 2 g/L, temperature of 10?C and initial diquat concentration of 50 mg/L. The time of electrolysis is 60 min for degradation rate of diquat and chemical oxygen demand (COD) removal is 210 min. The results were obtained by UV-Vis spectrophotometer and the present designed electrode was coincident.展开更多
A series of poly(aryl amine ketone)s have been obtained by the condensation polymerization of different aromatic dibromides with different primary aromatic diamines via palladium-catalyzed aryl amination reaction. The...A series of poly(aryl amine ketone)s have been obtained by the condensation polymerization of different aromatic dibromides with different primary aromatic diamines via palladium-catalyzed aryl amination reaction. The structures of polymers are characterized by means of FT-IR, 1H NMR spectroscopy, and elemental analysis. The results show an agreement with the proposed structures. DSC and TG measurements show that polymers possess high glass transition temperature (T g>170°C) and good thermal stability with high decomposition temperatures (T D>450°C). These novel polymers also exhibit good mechanical behaviors and good solubility.展开更多
文摘In the presence of equimolar triethylamine,vicinal dibromides were found to be easily debrominated by dibutyl telluride,forming the co- rresponding olefins.
基金National Natural Science Foundation of China (Grant No. 20772009)
文摘The fragmentation patterns of a series of dispirocyclopiperazinium dibromides with strong analgesic activity during positive ion electrospray ionization mass spectrometry were analyzed. The [M-Br]^＋ 2 ions showed the characteristic isotopic peaks and were assigned as the molecular ions. The loss of a 44 Dalton unit from 2 produced ion 3 [M-Br-44]^＋ and the loss of HBr from 2 formed ion 4. Besides, the carbamates 1d-1e produced extra ions [M-2Br-33]^＋. The related fragmentation mechanisms were proposed.
基金Project supported by the National Natural Science Foundation of China(No.29872010)the Natural Science Foundation of Zhejiang Province(No.298067)
文摘The ? ?vicinal dibromo carboxylic acid and its derivatives were debrominated with Sm/HOAc system to afford the corresponding cinnamic acid and its derivatives in good yields under mild conditions.
文摘The C/PbO2 electrode assisted electrochemical removal of diquat dibromide herbicides solutions has been the subject of the present investigation under several operating conditions. The optimum conditions of the treatment process are: current density of 150 mA/cm2, pH 2.2, NaCl concentration 2 g/L, temperature of 10?C and initial diquat concentration of 50 mg/L. The time of electrolysis is 60 min for degradation rate of diquat and chemical oxygen demand (COD) removal is 210 min. The results were obtained by UV-Vis spectrophotometer and the present designed electrode was coincident.
基金Supported by the National Natural Science Foundation of China (Grant No. 10576017).
文摘A series of poly(aryl amine ketone)s have been obtained by the condensation polymerization of different aromatic dibromides with different primary aromatic diamines via palladium-catalyzed aryl amination reaction. The structures of polymers are characterized by means of FT-IR, 1H NMR spectroscopy, and elemental analysis. The results show an agreement with the proposed structures. DSC and TG measurements show that polymers possess high glass transition temperature (T g>170°C) and good thermal stability with high decomposition temperatures (T D>450°C). These novel polymers also exhibit good mechanical behaviors and good solubility.
