Recently,continuous interests and persisting efforts on heteropolyniobate have been dedicated to its preparation and exploration.In this work,a novel Se-centred heteropolyniobate,[H2SeNb12(VO)4O40][Cu(en)2]2{[VNb12(VO...Recently,continuous interests and persisting efforts on heteropolyniobate have been dedicated to its preparation and exploration.In this work,a novel Se-centred heteropolyniobate,[H2SeNb12(VO)4O40][Cu(en)2]2{[VNb12(VO)4O40][Cu(en)2]4}0.5·39H2O(en=ethanediamine),was synthesized.The compound was synthesized in aqueous solution by reacting the K7HNb6O19·13H2O with a mixture of vanadate(Ⅴ) and selenite(Ⅳ) source,which consists of two polyanions,i.e.,V-centred one and Se-centred another.The architecture was characterized by infrared spectra,thermogravimetric analysis,X-ray powder diffraction spectroscopy,ultraviolet-visible and X-ray photoelectron spectroscopy.Further,the magnetic property shows the antiferromagnetic interaction of the compound.展开更多
Polyoxometalates(POMs),large oxoanions of the group 5 and 6 elements,attract attention due to their use as oxidation-stable catalysts and ligands.Different from the well-known V,Mo,and W POMs,the group V POMs of Ta as...Polyoxometalates(POMs),large oxoanions of the group 5 and 6 elements,attract attention due to their use as oxidation-stable catalysts and ligands.Different from the well-known V,Mo,and W POMs,the group V POMs of Ta assemble and are stable only in highly alkaline solution rather than acidic solution.In this paper,we successfully synthesized and structurally characterized two unprecedented peroxotantalum-containing clusters,KNa_(2)[HSe_(2)(TaO_(2))_(6)(OH)_(4)(H_(2)O)_(2)O_(13)]·15H_(2)O(1)and Cs_(2)K_(1.5)Na_(1.5)[Se_(4)(TaO_(2))_(6)(OH)_(3)O_(18)]·17H_(2)O(2),which comprises a 6-peroxo-6-tantalum core stabilized by two and four selenite centers,respectively.The simple,one-pot synthesis of 1 and 2 involving addition of sodium selenite into the acidified hexatantalate aqueous solution in the presence of hydrogen peroxide could represent a general procedure for incorporating heteroatoms into peroxo-polyoxotantalate species,thus opening new possibilities for this emergent branch of polyoxotantalate chemistry.Moreover,the catalytic properties of these two compounds were investigated using succinic anhydride and phenylamine as the model substrate,and compound 2 presents excellent catalytic activity in the amidation reactions of anhydrides and amines.展开更多
基金supported by the National Natural Science Foundation of China (22071045, 21671056)the Program for Science and Technology Innovation Talents in Universities of Henan Province (19HASTIT044)+4 种基金Excellent Youth Science Fund Project of Henan Province (202300410042)the StartUp Fund of Henan Universitythe Horizontal Cooperation Project of Nantong University (20ZH104)Science and Technology Program of Nantong (JC2020126)Project on the Cooperation of Industry,Education and Research of Jiangsu Province (BY2020556)。
文摘Recently,continuous interests and persisting efforts on heteropolyniobate have been dedicated to its preparation and exploration.In this work,a novel Se-centred heteropolyniobate,[H2SeNb12(VO)4O40][Cu(en)2]2{[VNb12(VO)4O40][Cu(en)2]4}0.5·39H2O(en=ethanediamine),was synthesized.The compound was synthesized in aqueous solution by reacting the K7HNb6O19·13H2O with a mixture of vanadate(Ⅴ) and selenite(Ⅳ) source,which consists of two polyanions,i.e.,V-centred one and Se-centred another.The architecture was characterized by infrared spectra,thermogravimetric analysis,X-ray powder diffraction spectroscopy,ultraviolet-visible and X-ray photoelectron spectroscopy.Further,the magnetic property shows the antiferromagnetic interaction of the compound.
基金financially supported by the National Natural Science Foundation of China (Grant Nos. 21671056 and 22071045)the Program for Science & Technology Innovation Talents in Universities of Henan Province (Grant No. 19HASTIT044)Excellent Youth Science Fund Project of Henan Province (Grant No. 202300410042)
文摘Polyoxometalates(POMs),large oxoanions of the group 5 and 6 elements,attract attention due to their use as oxidation-stable catalysts and ligands.Different from the well-known V,Mo,and W POMs,the group V POMs of Ta assemble and are stable only in highly alkaline solution rather than acidic solution.In this paper,we successfully synthesized and structurally characterized two unprecedented peroxotantalum-containing clusters,KNa_(2)[HSe_(2)(TaO_(2))_(6)(OH)_(4)(H_(2)O)_(2)O_(13)]·15H_(2)O(1)and Cs_(2)K_(1.5)Na_(1.5)[Se_(4)(TaO_(2))_(6)(OH)_(3)O_(18)]·17H_(2)O(2),which comprises a 6-peroxo-6-tantalum core stabilized by two and four selenite centers,respectively.The simple,one-pot synthesis of 1 and 2 involving addition of sodium selenite into the acidified hexatantalate aqueous solution in the presence of hydrogen peroxide could represent a general procedure for incorporating heteroatoms into peroxo-polyoxotantalate species,thus opening new possibilities for this emergent branch of polyoxotantalate chemistry.Moreover,the catalytic properties of these two compounds were investigated using succinic anhydride and phenylamine as the model substrate,and compound 2 presents excellent catalytic activity in the amidation reactions of anhydrides and amines.
