Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular...Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was studied.Biomass porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N precursors.Fe/Np Carbon was prepared simply by the high-temperature carbonization method.It was found that it showed the inherent catalysis properties for thermal decomposition of DAP-4.The heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p Carbon-0.The decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/mol.The possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.展开更多
Tin oxide nanociystals with diameters smaller than 10 nm were synthesized using Na2SnO3 and CO2 as reactants and cetyltrimethylammonium bromide(CTAB) as stabilizer under mild conditions.As a mild acidic gas,CO2 is f...Tin oxide nanociystals with diameters smaller than 10 nm were synthesized using Na2SnO3 and CO2 as reactants and cetyltrimethylammonium bromide(CTAB) as stabilizer under mild conditions.As a mild acidic gas,CO2 is favorable for the accurate adjustment of pH value of Na2SnO3 solution.Stannate salt is stable,cheap and easy in operation.The effects of Na2SnO3concentration,CTAB concentration,aging temperature,and aging time on the nanociystals were studied.It was found that,with the increasing Na2SnO3 concentration,aging temperature and aging time,SnO2 nanociystals size decreases.The formation of SnO2nanociystals can be interpreted by electrostatic-interaction mechanism.SnO2 nanociystals show high photocatalytic activities in the degradation of Rhodamine B solution.The catalytic activity of small nanocrystals is higher than that of large ones.展开更多
(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of po...(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization.展开更多
Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence...Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence of a citrate ligand, with an average flat size of approximately 10–15 μm. The important parameters, including the solution pH values and the concentration of the zinc ions and citrate ligand, were investigated using a series of experiments. It is verified that the citrate ligand significantly affects the morphology of zinc oxalate particles, probably via its multiple roles of chelating, dispersing, and selective absorption. Thermodynamic equilibrium of the distribution of zinc species in an aqueous solution of Zn(Ⅱ)-citrate-oxalate-H_2O was estimated to explain the experimental results and to clarify the size and morphological evolution mechanism of the precipitated particles.展开更多
The compound sulforaphane (SFN, 1) has been synthesized via a facile and green synthetic strategy based on the modification of previous methods. Because of its high bioactivities and rare content in nature, the pres...The compound sulforaphane (SFN, 1) has been synthesized via a facile and green synthetic strategy based on the modification of previous methods. Because of its high bioactivities and rare content in nature, the present work is of great important significance.展开更多
Nitroalkanes react smoothly with CF_3CCl_2COCH=CHPh via Michael addition in the presence of inorganic bases such as KF/Al2O3 or K2CO3, giving fluorinecontaining γ-nitro ketones in good yields.
4-Amino-4-deoxy-4′-demethylepipodophyllotoxin has been directly synthesized from 4′-demethylepipodophyllotoxin and HN_3 in the presence of BF3·Et_2O,followed by hydrogenation with palladium on charcoal as catal...4-Amino-4-deoxy-4′-demethylepipodophyllotoxin has been directly synthesized from 4′-demethylepipodophyllotoxin and HN_3 in the presence of BF3·Et_2O,followed by hydrogenation with palladium on charcoal as catalyst.展开更多
1. 2-Bispyrroleethylenes can be easily syntnesized bv cc,-,pt}ng pyrrolealdehyde using TiCl_4/Zn as a catalyst. It was found that when the R group is COMe or CO_2 Et, the product is a mixture of trans and cis isomers,...1. 2-Bispyrroleethylenes can be easily syntnesized bv cc,-,pt}ng pyrrolealdehyde using TiCl_4/Zn as a catalyst. It was found that when the R group is COMe or CO_2 Et, the product is a mixture of trans and cis isomers, and in the other cases, the products are pure trans isomers.展开更多
The insertion of dichlorocarbene generated from chloroform by Phase Transfer Catalysis(PTC)into carbon-boron bond of dialkylborate anions 3,obtained by method A and B,resulted in the formation of the inter- mediates 5...The insertion of dichlorocarbene generated from chloroform by Phase Transfer Catalysis(PTC)into carbon-boron bond of dialkylborate anions 3,obtained by method A and B,resulted in the formation of the inter- mediates 5,which were oxidized with alkaline hydrogen peroxide to give the corresponding dialkylketones in 36-77.9% yields.展开更多
In this paper,we report the chemical synthesis of oligonucleotide d-TGGGT using phosphotriester method.The protected pentamer d-MmtTGibGibGibT(=p-ClC6H_4-O(O)P)was deblocked by treatment with concentrated ammonium hyd...In this paper,we report the chemical synthesis of oligonucleotide d-TGGGT using phosphotriester method.The protected pentamer d-MmtTGibGibGibT(=p-ClC6H_4-O(O)P)was deblocked by treatment with concentrated ammonium hydroxide and 80% acetic acid.The pure d-TGGGT obtained by chromatorgraphy on DEAE-Sephadex A-25 and Q-Sepharose FF could be hydrolyzed completely and confirmed by base ratio.展开更多
The 1.3-dipolar cycloaddition reaction of 2-trifluoromethyl- oxazolone and the activated carbon-carbon multiple bond was studied and gave a convenient way to synthesize 2-trifluoromethylpyrrole derivatives.
Reaction of heterocycle substituted telluronium salts with aroma- tic aldehydes under mild conditions gave corresponding chalcones.In the presence of dibutyl telluride,2-bromomethyl-5-nitrofuran condensed easily with ...Reaction of heterocycle substituted telluronium salts with aroma- tic aldehydes under mild conditions gave corresponding chalcones.In the presence of dibutyl telluride,2-bromomethyl-5-nitrofuran condensed easily with aromatic aldehydes in THF to afford corresponding olefin derivatives as one-pot reaction.展开更多
A facile total synthesis of 6-pentyl-α-pyrone 1 has been described.The key step is the treatment of 2-furyl-pentyl-csrbinol 3 with NBS in aqueous tetrahydrofuran(THF).The overall yield is 34%.
A ffcile tatal synthesis of (±)-selina-3. 11-dien-9-ol (1) has been described. The key step is the onepot reductive fragmentation of α,β-unsaturated p-tosylhydrazone and deduction of 9-carbonyl of 5 With sodium...A ffcile tatal synthesis of (±)-selina-3. 11-dien-9-ol (1) has been described. The key step is the onepot reductive fragmentation of α,β-unsaturated p-tosylhydrazone and deduction of 9-carbonyl of 5 With sodium borohydride.展开更多
Some telluronium salts react easily with 1,4-bis(3-substituted phenyl-3-oxo-1-propenyl)benzene and 1,5-disubstituted phenyl-1,4-pentadien-3 -one to afford derivatives of biscyclopropanes in 61.8-88.8% yield.
s: The convenient synthesis of (-)-5αH.7β 10α-eudesmane-3. 11-dielle 1 has been achieved in four steps starting from R-(-)-carvone. The key step is the reductive deoxygenation of α,β-unsaturated tosylhydrazone to...s: The convenient synthesis of (-)-5αH.7β 10α-eudesmane-3. 11-dielle 1 has been achieved in four steps starting from R-(-)-carvone. The key step is the reductive deoxygenation of α,β-unsaturated tosylhydrazone together with the migration of the double bond.展开更多
基金National Natural Science Foundation of China(Grant No.21975227)the Found of National defence Science and Technology Key Laboratory (Grant No.6142602210306)。
文摘Fe/N-based biomass porous carbon composite(Fe/N-p Carbon) was prepared by a facile high-temperature carbonization method from biomass,and the effect of Fe/N-p Carbon on the thermal decomposition of energetic molecular perovskite-based material DAP-4 was studied.Biomass porous carbonaceous materials was considered as the micro/nano support layers for in situ deposition of Fe/N precursors.Fe/Np Carbon was prepared simply by the high-temperature carbonization method.It was found that it showed the inherent catalysis properties for thermal decomposition of DAP-4.The heat release of DAP-4/Fe/N-p Carbon by DSC curves tested had increased slightly,compared from DAP-4/Fe/N-p Carbon-0.The decomposition temperature peak of DAP-4 at the presence of Fe/N-p Carbon had reduced by 79°C from384.4°C(pure DAP-4) to 305.4°C(DAP-4/Fe/N-p Carbon-3).The apparent activation energy of DAP-4thermal decomposition also had decreased by 29.1 J/mol.The possible catalytic decomposition mechanism of DAP-4 with Fe/N-p Carbon was proposed.
基金Projects (20676016,21076024) supported by the National Natural Science Foundation of China
文摘Tin oxide nanociystals with diameters smaller than 10 nm were synthesized using Na2SnO3 and CO2 as reactants and cetyltrimethylammonium bromide(CTAB) as stabilizer under mild conditions.As a mild acidic gas,CO2 is favorable for the accurate adjustment of pH value of Na2SnO3 solution.Stannate salt is stable,cheap and easy in operation.The effects of Na2SnO3concentration,CTAB concentration,aging temperature,and aging time on the nanociystals were studied.It was found that,with the increasing Na2SnO3 concentration,aging temperature and aging time,SnO2 nanociystals size decreases.The formation of SnO2nanociystals can be interpreted by electrostatic-interaction mechanism.SnO2 nanociystals show high photocatalytic activities in the degradation of Rhodamine B solution.The catalytic activity of small nanocrystals is higher than that of large ones.
文摘(a)NCA polymerization initiated by LiHMDS or other initiators in THF,initiator i)n-hexylamine,ii)HMDS,iii)bipyNi(COD);(b)LiHMDS-initiated open vessel polymerization of BLGNCA at 26 mg and 2 g scale;(c)GPC traces of poly-BLG at variable DP;(d)Reaction rates of LiHMDS and hexylamine initiated BLGNCA polymerization in THF with NCA:initiator ratio of 100∶1 and initial NCA concentration at 0.2 mol/L;(e)CD spectra of poly-BLG at variable DP prepared from LiHMDS-initiated NCA polymerization.
文摘Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
文摘Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence of a citrate ligand, with an average flat size of approximately 10–15 μm. The important parameters, including the solution pH values and the concentration of the zinc ions and citrate ligand, were investigated using a series of experiments. It is verified that the citrate ligand significantly affects the morphology of zinc oxalate particles, probably via its multiple roles of chelating, dispersing, and selective absorption. Thermodynamic equilibrium of the distribution of zinc species in an aqueous solution of Zn(Ⅱ)-citrate-oxalate-H_2O was estimated to explain the experimental results and to clarify the size and morphological evolution mechanism of the precipitated particles.
基金supported by the National Natural Science Foundation of China(No.20472025 and No.20021001).
文摘The compound sulforaphane (SFN, 1) has been synthesized via a facile and green synthetic strategy based on the modification of previous methods. Because of its high bioactivities and rare content in nature, the present work is of great important significance.
文摘Nitroalkanes react smoothly with CF_3CCl_2COCH=CHPh via Michael addition in the presence of inorganic bases such as KF/Al2O3 or K2CO3, giving fluorinecontaining γ-nitro ketones in good yields.
文摘4-Amino-4-deoxy-4′-demethylepipodophyllotoxin has been directly synthesized from 4′-demethylepipodophyllotoxin and HN_3 in the presence of BF3·Et_2O,followed by hydrogenation with palladium on charcoal as catalyst.
文摘1. 2-Bispyrroleethylenes can be easily syntnesized bv cc,-,pt}ng pyrrolealdehyde using TiCl_4/Zn as a catalyst. It was found that when the R group is COMe or CO_2 Et, the product is a mixture of trans and cis isomers, and in the other cases, the products are pure trans isomers.
文摘The insertion of dichlorocarbene generated from chloroform by Phase Transfer Catalysis(PTC)into carbon-boron bond of dialkylborate anions 3,obtained by method A and B,resulted in the formation of the inter- mediates 5,which were oxidized with alkaline hydrogen peroxide to give the corresponding dialkylketones in 36-77.9% yields.
文摘In this paper,we report the chemical synthesis of oligonucleotide d-TGGGT using phosphotriester method.The protected pentamer d-MmtTGibGibGibT(=p-ClC6H_4-O(O)P)was deblocked by treatment with concentrated ammonium hydroxide and 80% acetic acid.The pure d-TGGGT obtained by chromatorgraphy on DEAE-Sephadex A-25 and Q-Sepharose FF could be hydrolyzed completely and confirmed by base ratio.
文摘The 1.3-dipolar cycloaddition reaction of 2-trifluoromethyl- oxazolone and the activated carbon-carbon multiple bond was studied and gave a convenient way to synthesize 2-trifluoromethylpyrrole derivatives.
文摘Reaction of heterocycle substituted telluronium salts with aroma- tic aldehydes under mild conditions gave corresponding chalcones.In the presence of dibutyl telluride,2-bromomethyl-5-nitrofuran condensed easily with aromatic aldehydes in THF to afford corresponding olefin derivatives as one-pot reaction.
文摘A facile total synthesis of 6-pentyl-α-pyrone 1 has been described.The key step is the treatment of 2-furyl-pentyl-csrbinol 3 with NBS in aqueous tetrahydrofuran(THF).The overall yield is 34%.
文摘A ffcile tatal synthesis of (±)-selina-3. 11-dien-9-ol (1) has been described. The key step is the onepot reductive fragmentation of α,β-unsaturated p-tosylhydrazone and deduction of 9-carbonyl of 5 With sodium borohydride.
文摘Some telluronium salts react easily with 1,4-bis(3-substituted phenyl-3-oxo-1-propenyl)benzene and 1,5-disubstituted phenyl-1,4-pentadien-3 -one to afford derivatives of biscyclopropanes in 61.8-88.8% yield.
文摘s: The convenient synthesis of (-)-5αH.7β 10α-eudesmane-3. 11-dielle 1 has been achieved in four steps starting from R-(-)-carvone. The key step is the reductive deoxygenation of α,β-unsaturated tosylhydrazone together with the migration of the double bond.