The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2(3H)- yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-ox...The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2(3H)- yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469(2), b = 16.7715(5), c = 13.7153(4) A, β= 104.9680(10)°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08(10) ,A3, Z= 4, Dc = 1.376 g/cm3, F(000) = 904, T= 296(2) K, R = 0.0508 and wR = 0.1478.展开更多
A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigate...A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigated to optimize the oxidation of HMF into DFF. It was found that the reaction solvent was very crucial for this reaction. Trifluoroacetic acid was the best solvent for the oxidation of HMF into DFF by Na NO2.Under the optimal reaction condition, almost quantitative HMF conversion and high DFF yield of 90.4% were obtained after 1 h at room temperature.展开更多
A two-channel electrochemical quartz crystal microbalance (EQCM) was used to investigate the cyclic voltammetric behavior of two Prussian blue (PB) film-modified Au electrodes in a two-electrode con-figuration in aque...A two-channel electrochemical quartz crystal microbalance (EQCM) was used to investigate the cyclic voltammetric behavior of two Prussian blue (PB) film-modified Au electrodes in a two-electrode con-figuration in aqueous solution. The redox peaks observed in the two-electrode cyclic voltammogram (CV) are assigned to the intrinsic redox transitions among the Everitt's salt, PB, and Prussian yellow for the film itself, the redox process of the Au substrate and the redox process of small-quantity ferri-/ferrocyanide impurities entrapped in the PB film, as also supported by ultraviolet-visible (UV-Vis) spectroelectrochemical data. The profile of the two-electrode solid-state CV for the PB powder sand-wiched between two gold-coated indium-tin oxide (ITO) electrodes is similar to that for two PB-modified Au electrodes in aqueous solution, implying similar origins for the corresponding redox peaks. The two-channel EQCM method is expected to become a highly effective technique for the studies of the two-electrode electrochemical behaviors of many other species/materials.展开更多
A series of multi-(phe nylthio)porphyrinato Ni(Ⅱ) compounds were synthesized without the participation of transition metal catalysts.All of these products were well characterized by 1 H NMR,13C NMR and HRMS.Structure...A series of multi-(phe nylthio)porphyrinato Ni(Ⅱ) compounds were synthesized without the participation of transition metal catalysts.All of these products were well characterized by 1 H NMR,13C NMR and HRMS.Structures of three typical compounds were further confirmed by X-ray single crystal diffraction.Remarkable red shifts were observed in UV-vis absorption spectra of multi-(phenylthio)porphyrinato Ni(Ⅱ) compounds which meet well with the electrochemical data.DFT calculation indicates that the phenylthio groups have strong effects on the frontier orbitals of these molecules.The order of a_(1u)-like and a_(2u)-like orbitals mainly distributed in porphyrin moiety is often inversed in energy when multiphenylthio groups are attached.展开更多
Buchwald-Hartwig amination of 5,15-dibromo and 5,10-dibromo Ni(Ⅱ)porphyrins with 5-amino Ni(Ⅱ)porphyrin gave linear and bent trimers 4Ni and 5Ni with a central quinodiimine-type Ni(Ⅱ)porphyrinoid.The structures of ...Buchwald-Hartwig amination of 5,15-dibromo and 5,10-dibromo Ni(Ⅱ)porphyrins with 5-amino Ni(Ⅱ)porphyrin gave linear and bent trimers 4Ni and 5Ni with a central quinodiimine-type Ni(Ⅱ)porphyrinoid.The structures of 4Ni and 5Ni have been confirmed by X-ray diffraction analysis in both cases.The formation of unusual products 4Ni and 5Ni has been ascribed to facile oxidation of 5,15-and 5,10-amino Ni(Ⅱ)porphyrin unit.Reduction of 4Ni and 5Ni under proper conditions gave NH-bridged Ni(Ⅱ)porphyrin trimers 4Ni-2H and 5Ni-2H in high yields.Trimers 4Ni and 5Ni exhibit the lowest energy band as compared with 4Ni-2H and 5Ni-2H.Especially the bent trimer 5Ni exhibits a broad absorption tail beyond 1400 nm.展开更多
6,6"-Terpyridylene bridged cyclic porphyrin dimer 2Ni, trimer 3Ni, tetramer 4Ni and pentamer 5Ni were obtained through Suzuki-Miyaura coupling reaction of/~,jB'-diboryl Ni(II) porphyrin with 6,6"-dibromo- 2,2':...6,6"-Terpyridylene bridged cyclic porphyrin dimer 2Ni, trimer 3Ni, tetramer 4Ni and pentamer 5Ni were obtained through Suzuki-Miyaura coupling reaction of/~,jB'-diboryl Ni(II) porphyrin with 6,6"-dibromo- 2,2':6',2"-terpyridine. Free base porphyrin nanorings 2H-SH were obtained by demetallation of 2Ni-SNi with sulfuric acid in CHCI3 and then were converted into 2Zn-SZn upon treatment with Zn(OAc)2 in quantitative yields, respectively. All of these newly synthesized porphyrin nanorings were characterized by high-resolution mass spectrometry and 1H NMR spectroscopy. The photophysical properties of porphyrin nanoring were examined by UV-vis and fluorescence spectra. The electrochemical properties of 2Ni-SNi were investigated by cyclic voltammetry and differential pulse voltammetry. The UV-vis absorption spectra and fluorescence spectra of these cyclic porphyrin arrays indicate that there exist unique electronic interactions between the constituent porphyrin units in each ring. Electrochemical analysis shows that the trimer 3Ni exhibit different redox behavior, which indicate that the porphyrin units in 3Ni are presumably more coplanar than in other cyclic oorohvrin arrays.展开更多
基金Supported by the National Natural Science Foundation of China (20872033, 20575019)Natural Science Foundation of Hunan Province (07JJ1003)+1 种基金Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China) (KLCBTCMR2008-14)Scientific Research Fund of Science and Technology Department of Hunan Province (No. 2006GK3067)
文摘The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-lH-isoindol-2(3H)- yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate with 4,5,6,7- tetraydrophthalic anhydride, and its structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P2 1/n with a = 9.3469(2), b = 16.7715(5), c = 13.7153(4) A, β= 104.9680(10)°, μ = 0.107 mm^-1, Mr = 430.42, V= 2077.08(10) ,A3, Z= 4, Dc = 1.376 g/cm3, F(000) = 904, T= 296(2) K, R = 0.0508 and wR = 0.1478.
基金supported by the National Natural Science Foundation of China(21272065)Scientific Research Fund of Hunan Provincial Education Department(13C562+2 种基金15C0816)Outstanding Youth Project of Hunan Provincial Education Department(15B134)the funding offered by China Scholarship Council(201506720018)
文摘A mild and simple process for the effective oxidation of 5-hydroxymethylfurfural(HMF) into 2,5-diformylfuran(DFF) has been developed using Na NO2 as the oxidant. Some important reaction parameters were investigated to optimize the oxidation of HMF into DFF. It was found that the reaction solvent was very crucial for this reaction. Trifluoroacetic acid was the best solvent for the oxidation of HMF into DFF by Na NO2.Under the optimal reaction condition, almost quantitative HMF conversion and high DFF yield of 90.4% were obtained after 1 h at room temperature.
基金the National Natural Science Foundation of China (Grant Nos. 20675029, 90713018 & 20335020)the Foundation of the Ministry of Education of China (jiaorensi[2000]26, jiaojisi[2000]65)+1 种基金Hunan Provincial Educational Department (05K009, 05A036)State Key Laboratory of Electroanalytical Chemistry
文摘A two-channel electrochemical quartz crystal microbalance (EQCM) was used to investigate the cyclic voltammetric behavior of two Prussian blue (PB) film-modified Au electrodes in a two-electrode con-figuration in aqueous solution. The redox peaks observed in the two-electrode cyclic voltammogram (CV) are assigned to the intrinsic redox transitions among the Everitt's salt, PB, and Prussian yellow for the film itself, the redox process of the Au substrate and the redox process of small-quantity ferri-/ferrocyanide impurities entrapped in the PB film, as also supported by ultraviolet-visible (UV-Vis) spectroelectrochemical data. The profile of the two-electrode solid-state CV for the PB powder sand-wiched between two gold-coated indium-tin oxide (ITO) electrodes is similar to that for two PB-modified Au electrodes in aqueous solution, implying similar origins for the corresponding redox peaks. The two-channel EQCM method is expected to become a highly effective technique for the studies of the two-electrode electrochemical behaviors of many other species/materials.
基金supported by the National Nature Science Foundation of China (Nos.21702057,21772036,and 21602058)the Scientific Research Fund of Hunan Provincial Science and Technology Department (No.2017JJ3199)+1 种基金Science and Technology Planning Project of Hunan Province (No.2018TP1017)the Opening Fund of Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China)。
文摘A series of multi-(phe nylthio)porphyrinato Ni(Ⅱ) compounds were synthesized without the participation of transition metal catalysts.All of these products were well characterized by 1 H NMR,13C NMR and HRMS.Structures of three typical compounds were further confirmed by X-ray single crystal diffraction.Remarkable red shifts were observed in UV-vis absorption spectra of multi-(phenylthio)porphyrinato Ni(Ⅱ) compounds which meet well with the electrochemical data.DFT calculation indicates that the phenylthio groups have strong effects on the frontier orbitals of these molecules.The order of a_(1u)-like and a_(2u)-like orbitals mainly distributed in porphyrin moiety is often inversed in energy when multiphenylthio groups are attached.
基金supported by the National Natural Science Foundation of China(Nos.21772036,22071052,21602058,21702057)the Science and Technology Planning Project of Hunan Province(No.2018TP1017)+1 种基金the Scientific Research Fund of Hunan Provincial Education Department(No.19A331)Hunan Provincial Innovation Foundation for Postgraduate(No.CX20210473)。
文摘Buchwald-Hartwig amination of 5,15-dibromo and 5,10-dibromo Ni(Ⅱ)porphyrins with 5-amino Ni(Ⅱ)porphyrin gave linear and bent trimers 4Ni and 5Ni with a central quinodiimine-type Ni(Ⅱ)porphyrinoid.The structures of 4Ni and 5Ni have been confirmed by X-ray diffraction analysis in both cases.The formation of unusual products 4Ni and 5Ni has been ascribed to facile oxidation of 5,15-and 5,10-amino Ni(Ⅱ)porphyrin unit.Reduction of 4Ni and 5Ni under proper conditions gave NH-bridged Ni(Ⅱ)porphyrin trimers 4Ni-2H and 5Ni-2H in high yields.Trimers 4Ni and 5Ni exhibit the lowest energy band as compared with 4Ni-2H and 5Ni-2H.Especially the bent trimer 5Ni exhibits a broad absorption tail beyond 1400 nm.
基金supported by the National Natural Science Foundation of China(No. 21272065)the Opening Fund of Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research(Ministry of Education of China),Hunan Normal University(No. KLCBTCMR2015-07)+2 种基金the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education MinistryScientific Research Fund of Hunan Provincial Education Department(No. 16A125)the National Natural Science Foundation of China(No. 21602058)
文摘6,6"-Terpyridylene bridged cyclic porphyrin dimer 2Ni, trimer 3Ni, tetramer 4Ni and pentamer 5Ni were obtained through Suzuki-Miyaura coupling reaction of/~,jB'-diboryl Ni(II) porphyrin with 6,6"-dibromo- 2,2':6',2"-terpyridine. Free base porphyrin nanorings 2H-SH were obtained by demetallation of 2Ni-SNi with sulfuric acid in CHCI3 and then were converted into 2Zn-SZn upon treatment with Zn(OAc)2 in quantitative yields, respectively. All of these newly synthesized porphyrin nanorings were characterized by high-resolution mass spectrometry and 1H NMR spectroscopy. The photophysical properties of porphyrin nanoring were examined by UV-vis and fluorescence spectra. The electrochemical properties of 2Ni-SNi were investigated by cyclic voltammetry and differential pulse voltammetry. The UV-vis absorption spectra and fluorescence spectra of these cyclic porphyrin arrays indicate that there exist unique electronic interactions between the constituent porphyrin units in each ring. Electrochemical analysis shows that the trimer 3Ni exhibit different redox behavior, which indicate that the porphyrin units in 3Ni are presumably more coplanar than in other cyclic oorohvrin arrays.