Wells-dawson type heteropolyacid catalyst was prepared by acidification-etherization and characterized by FTIR,over which cyclohexanone ethylene ketal was synthesized from cyclohexanone to ethylene.The experiment resu...Wells-dawson type heteropolyacid catalyst was prepared by acidification-etherization and characterized by FTIR,over which cyclohexanone ethylene ketal was synthesized from cyclohexanone to ethylene.The experiment results showed that the optimal reaction conditions are as follows:the amount of Cyclohexanone is 0.1mol,the molar ratio of Cyclohexanone to ethylene was1.0/1.5(mol/mol),catalyst amount 1.50%(pencent of the reaction stock materials).Through reaction time 2.5h,the yield of cyclohexanone ethylene katal reached over 95.0%.展开更多
Polyoxometalates（POMs） with Cd-coordination complexes acting as supporting units are rarely reported. The linkage of the supporting units with inorganic building block（polyanion） is generally established on termin...Polyoxometalates（POMs） with Cd-coordination complexes acting as supporting units are rarely reported. The linkage of the supporting units with inorganic building block（polyanion） is generally established on terminal O-atoms, but scarcely via bridging O-atoms. By introducing liquid small organic molecule（pyridine, C5NH5） as assistant ＂structure-directing agent＂, we obtained a novel organic-inorganic hybrid polytungstate,（Hpy）4[Cd（phen）2（P2W18O62）]·nH2O（1, n ≈ 3, py = pyridine, phen = 1,10-phenanthroline）, under hydrothermal conditions. The single-crystal X-ray diffraction analysis shows that 1 is the first compound containing an asymmetric heteropolyanion, [Cd（phen）2（P2W18O62）]4–, a Wells-Dawson-type polyanion monosupported by Cd-coordination complex via di-bridging O-atoms.展开更多
The multicomponent condensation of an aryl aldehyde,acetyl chloride,acetonitrile,and enolizable ketone as one-pot synthesis of β-acetamido ketones in high yields was investigated using commercial,non-corrosive,and en...The multicomponent condensation of an aryl aldehyde,acetyl chloride,acetonitrile,and enolizable ketone as one-pot synthesis of β-acetamido ketones in high yields was investigated using commercial,non-corrosive,and environmentally benign Keggin and Wells-Dawson heteropolyacid catalysts.The best catalyst was H5PW10V2O40.The methodology used simple experimental conditions,and the short reaction times and high yields indicate it is a useful strategy for the large scale synthesis of β-acetamido ketones.展开更多
Polyoxometalate （POM）-based materials universally have some inherent flaws, including low recovery, metastability, solubility, etc., which may restrict their practical applications. Modifying the materials with orga...Polyoxometalate （POM）-based materials universally have some inherent flaws, including low recovery, metastability, solubility, etc., which may restrict their practical applications. Modifying the materials with organic-inorganic hybrid complexes is one of the most effective approaches to overcome these deficiencies. Under hydrothermal conditions, a new Wells- Dawson-type polytungstate modified Cd-complex, [Cd（phen）3]3[W18O54（PO4）2]？3H2O （1, phen = 1,10-phenanthroline （C12N2H8））, has been synthesized by selecting Cd2＋ coordinated phen and employing stepwise self-assembly plans. The compound shows good stability and water- insolubility under normal circumstances. Experiments demonstrate that compound 1 has ideal catalytic activity in the degradation reaction of rhodamine B （RhB） under ultraviolet （UV）-light and oxidant H2O2 conditions. Detailed characterizations including X-ray single-crystal diffraction （XRD）, Powder X-ray diffraction （PXRD）, elemental analysis, energy-dispersive X-ray spectroscopy （EDS） analyses, Fourier transform infrared spectroscopy （FT-IR）, UV-Vis-NIR diffuse reflection spectrum （DRS） and XPS spectrum are presented herein. The electrochemical （cyclic voltammetry （CV）） and photocatalytic properties of 1 have also been studied.展开更多
研究了在HY型分子筛的超笼结构中原位合成Wells-Dawson型磷钨酸,并作为催化剂用于液相甘油脱水制备丙烯醛反应。通过FTIR、31P MAS NMR表征,证明磷钨酸被成功合成在超笼结构中,避免了采用普通浸渍法制备的磷钨酸/HY催化剂存在的活性组...研究了在HY型分子筛的超笼结构中原位合成Wells-Dawson型磷钨酸,并作为催化剂用于液相甘油脱水制备丙烯醛反应。通过FTIR、31P MAS NMR表征,证明磷钨酸被成功合成在超笼结构中,避免了采用普通浸渍法制备的磷钨酸/HY催化剂存在的活性组分易流失的缺点,催化剂稳定性显著提高。展开更多
文摘Wells-dawson type heteropolyacid catalyst was prepared by acidification-etherization and characterized by FTIR,over which cyclohexanone ethylene ketal was synthesized from cyclohexanone to ethylene.The experiment results showed that the optimal reaction conditions are as follows:the amount of Cyclohexanone is 0.1mol,the molar ratio of Cyclohexanone to ethylene was1.0/1.5(mol/mol),catalyst amount 1.50%(pencent of the reaction stock materials).Through reaction time 2.5h,the yield of cyclohexanone ethylene katal reached over 95.0%.
基金supported by the Foundation of Education Department of Fujian Province(Nos.JB12199 and JA11245)the National Natural Science Foundation of China(Nos.21233004 and 40972035)
文摘Polyoxometalates（POMs） with Cd-coordination complexes acting as supporting units are rarely reported. The linkage of the supporting units with inorganic building block（polyanion） is generally established on terminal O-atoms, but scarcely via bridging O-atoms. By introducing liquid small organic molecule（pyridine, C5NH5） as assistant ＂structure-directing agent＂, we obtained a novel organic-inorganic hybrid polytungstate,（Hpy）4[Cd（phen）2（P2W18O62）]·nH2O（1, n ≈ 3, py = pyridine, phen = 1,10-phenanthroline）, under hydrothermal conditions. The single-crystal X-ray diffraction analysis shows that 1 is the first compound containing an asymmetric heteropolyanion, [Cd（phen）2（P2W18O62）]4–, a Wells-Dawson-type polyanion monosupported by Cd-coordination complex via di-bridging O-atoms.
基金Partial financial support from the Research Council of Sabzevar Tarbiat Moallem University is greatly appreciated
文摘The multicomponent condensation of an aryl aldehyde,acetyl chloride,acetonitrile,and enolizable ketone as one-pot synthesis of β-acetamido ketones in high yields was investigated using commercial,non-corrosive,and environmentally benign Keggin and Wells-Dawson heteropolyacid catalysts.The best catalyst was H5PW10V2O40.The methodology used simple experimental conditions,and the short reaction times and high yields indicate it is a useful strategy for the large scale synthesis of β-acetamido ketones.
基金supported by the Natural Science Foundation of Fujian Province(No.2017J01583)the College Students’Entrepreneurial Innovation Plan of Fujian Province(No.201511312052)+2 种基金the Drs.Scientific Research Start-up Foundation of Longyan University(No.LB2014021)Fujian Provincial Key Laboratory of Advanced Materials(Xiamen University)Key Subject Building Project of Longyan University
文摘Polyoxometalate （POM）-based materials universally have some inherent flaws, including low recovery, metastability, solubility, etc., which may restrict their practical applications. Modifying the materials with organic-inorganic hybrid complexes is one of the most effective approaches to overcome these deficiencies. Under hydrothermal conditions, a new Wells- Dawson-type polytungstate modified Cd-complex, [Cd（phen）3]3[W18O54（PO4）2]？3H2O （1, phen = 1,10-phenanthroline （C12N2H8））, has been synthesized by selecting Cd2＋ coordinated phen and employing stepwise self-assembly plans. The compound shows good stability and water- insolubility under normal circumstances. Experiments demonstrate that compound 1 has ideal catalytic activity in the degradation reaction of rhodamine B （RhB） under ultraviolet （UV）-light and oxidant H2O2 conditions. Detailed characterizations including X-ray single-crystal diffraction （XRD）, Powder X-ray diffraction （PXRD）, elemental analysis, energy-dispersive X-ray spectroscopy （EDS） analyses, Fourier transform infrared spectroscopy （FT-IR）, UV-Vis-NIR diffuse reflection spectrum （DRS） and XPS spectrum are presented herein. The electrochemical （cyclic voltammetry （CV）） and photocatalytic properties of 1 have also been studied.
