The benzophenone-initiated photoaddition of N-methyl ammes 2 to the chiral synthon1 proceeds in a regiospecitlc and highlyr stereocontrolled thshion to give the C-C photoadductscontaining a ne\viy stereogenic center 3...The benzophenone-initiated photoaddition of N-methyl ammes 2 to the chiral synthon1 proceeds in a regiospecitlc and highlyr stereocontrolled thshion to give the C-C photoadductscontaining a ne\viy stereogenic center 3a-3c. The enantiomerically pure N-C photoadducts, aminobutenolides 5a-5c have been obtained from the enantioselective photoaddition of secondary cyclicammes 4 with the chiral synthon 1 under the same conditions.展开更多
Heterogeneous photocatalysed reduction of aqueous Na_2CO_3 was carried out by using nano LaCoO_3 semiconductor powders. Formic acid and formaldehyde were identified as photoproducts,and were measured spectrophotometri...Heterogeneous photocatalysed reduction of aqueous Na_2CO_3 was carried out by using nano LaCoO_3 semiconductor powders. Formic acid and formaldehyde were identified as photoproducts,and were measured spectrophotometrically using Nash reagent. The effect of different parameters such as sodium carbonate concentration,amount of photocatalyst and different light sources on the yield of photoproducts was also investigated. It shows that nano LaCoO_3 has photocatalytic activity. Irradiation leads to the production of electrons in the conduction band of the LaCoO_3 semiconductor. It is likely that the photoproduced electrons initially reduce CO_3 (2-) to HCOO -,and then to HCHO and CH_3OH.展开更多
Heterogenous photocatalyzed reduction of aqueous Na2CO3 has been carried out by using nano SrFeO3 semiconductor powders. Formic acid, formaldehyde and methyl alcohol were identified as photoproducts, and were measure...Heterogenous photocatalyzed reduction of aqueous Na2CO3 has been carried out by using nano SrFeO3 semiconductor powders. Formic acid, formaldehyde and methyl alcohol were identified as photoproducts, and were measured spectrophotometrically. The effect of the variation of different parameters such as sodium carbonate concentration, amount of photocatalyst and different light sources on the yield of photoproducts was also investigated. It shows that nano SrFeO3 has photocatalytic activity. Irradiation leads to the production of electrons in the conduction band of the SrFeO3 semiconductor. It is likely that the photoproduced electrons reduce CO32- initially to HCOO-, and then to HCHO and CH3OH.展开更多
文摘The benzophenone-initiated photoaddition of N-methyl ammes 2 to the chiral synthon1 proceeds in a regiospecitlc and highlyr stereocontrolled thshion to give the C-C photoadductscontaining a ne\viy stereogenic center 3a-3c. The enantiomerically pure N-C photoadducts, aminobutenolides 5a-5c have been obtained from the enantioselective photoaddition of secondary cyclicammes 4 with the chiral synthon 1 under the same conditions.
文摘Heterogeneous photocatalysed reduction of aqueous Na_2CO_3 was carried out by using nano LaCoO_3 semiconductor powders. Formic acid and formaldehyde were identified as photoproducts,and were measured spectrophotometrically using Nash reagent. The effect of different parameters such as sodium carbonate concentration,amount of photocatalyst and different light sources on the yield of photoproducts was also investigated. It shows that nano LaCoO_3 has photocatalytic activity. Irradiation leads to the production of electrons in the conduction band of the LaCoO_3 semiconductor. It is likely that the photoproduced electrons initially reduce CO_3 (2-) to HCOO -,and then to HCHO and CH_3OH.
基金The authors are grateful to the National Natural Science Foundation of China for financial support.
文摘Heterogenous photocatalyzed reduction of aqueous Na2CO3 has been carried out by using nano SrFeO3 semiconductor powders. Formic acid, formaldehyde and methyl alcohol were identified as photoproducts, and were measured spectrophotometrically. The effect of the variation of different parameters such as sodium carbonate concentration, amount of photocatalyst and different light sources on the yield of photoproducts was also investigated. It shows that nano SrFeO3 has photocatalytic activity. Irradiation leads to the production of electrons in the conduction band of the SrFeO3 semiconductor. It is likely that the photoproduced electrons reduce CO32- initially to HCOO-, and then to HCHO and CH3OH.
