Dendrimers are the subject of intense attention recently because of their anticipated potentialities and the peculiar structural properties.A novel synthetic route for the preparation of functionalized dendrons built ...Dendrimers are the subject of intense attention recently because of their anticipated potentialities and the peculiar structural properties.A novel synthetic route for the preparation of functionalized dendrons built on the 1,3,5-benzenetricarboxaldehyde core and endowed with a periphery of pentaerythritol groups has been developed.1,3,5-Tri（2,6-dioxa-4,4-dihydroxymethyl cyclohexyl） benzene（1） was synthesized by the condensation of 1,3,5-benzenetricarboxaldehyde with pentaerythritol in the presence of hot CHCl3 and p-methyl benzene sulfonic acid with 55% yield.By turning 1,3,5-benzenetricarboxaldehyde into its trioxime,it was protected to decrease the cross-linked reaction with compound 1 both including many groups.The reaction of compound 1 with 1,3,5-benzenetricarboxaldehyde trioxime and pentaerythritol afforded 1,3,5-tri{3-[2,4,8,10 -tetra-oxa-9(3,5-di（2,6-dioxa-4,4-dihydroxymethylcyclohexyl） phenyl]spiro\undecyl}benzene（2） by using I2 as the catalyst,and the yield was 25.2%.Product 2 and its intermediates were identified by IR,1H NMR,MS spectra and elemental analysis.展开更多
Increasing the 1,3,5-trioxane(TOX) concentration in the equilibrated vapor phase of TOX-H_(2)O system has been recognized as a challenge for the azeotrope. Ionic liquids(ILs) were used to improve the relative volatili...Increasing the 1,3,5-trioxane(TOX) concentration in the equilibrated vapor phase of TOX-H_(2)O system has been recognized as a challenge for the azeotrope. Ionic liquids(ILs) were used to improve the relative volatility of TOX to H_(2)O and destroy the azeotrope in the TOX-H2O system. The vapor-liquid equilibrium of TOX-H2O system at 101.3 kPa was studied with the addition of 1-butyl-3-methylimidazolium hydrogen sulfate, 1-hexyl-3-methylimidazolium hydrogen sulfate and 1-butyl-3-methylimidazolium nitrate, respectively. The results showed that the volatility of TOX increased with the increase in IL dosage. And the volatility of water decreased with the increase in IL dosage. The relative volatility of TOX to H_(2)O was improved with the increase in ILs dosage. The azeotrope could be destroyed with an IL mole fraction of about 0.10. A non-random two-liquid(NRTL) model was successfully used to correlate the experimental data. The interaction parameters were obtained by fitting the experimental data with the model. The results indicated that a strong interaction existed between ILs and water. The strong interaction improved the volatility of TOX and inhibited the volatility of water, and then intensified the relative volatility of TOX to H_(2)O. The results showed that an ILs with strong polarity and hydrophilicity may be a potential additive to improve the TOX concentration in the equilibrated vapor phase.展开更多
文摘Dendrimers are the subject of intense attention recently because of their anticipated potentialities and the peculiar structural properties.A novel synthetic route for the preparation of functionalized dendrons built on the 1,3,5-benzenetricarboxaldehyde core and endowed with a periphery of pentaerythritol groups has been developed.1,3,5-Tri（2,6-dioxa-4,4-dihydroxymethyl cyclohexyl） benzene（1） was synthesized by the condensation of 1,3,5-benzenetricarboxaldehyde with pentaerythritol in the presence of hot CHCl3 and p-methyl benzene sulfonic acid with 55% yield.By turning 1,3,5-benzenetricarboxaldehyde into its trioxime,it was protected to decrease the cross-linked reaction with compound 1 both including many groups.The reaction of compound 1 with 1,3,5-benzenetricarboxaldehyde trioxime and pentaerythritol afforded 1,3,5-tri{3-[2,4,8,10 -tetra-oxa-9(3,5-di（2,6-dioxa-4,4-dihydroxymethylcyclohexyl） phenyl]spiro\undecyl}benzene（2） by using I2 as the catalyst,and the yield was 25.2%.Product 2 and its intermediates were identified by IR,1H NMR,MS spectra and elemental analysis.
基金supported by the fundamental research funds for the central universities(2022SCUH0041,SCU2023D012).
文摘Increasing the 1,3,5-trioxane(TOX) concentration in the equilibrated vapor phase of TOX-H_(2)O system has been recognized as a challenge for the azeotrope. Ionic liquids(ILs) were used to improve the relative volatility of TOX to H_(2)O and destroy the azeotrope in the TOX-H2O system. The vapor-liquid equilibrium of TOX-H2O system at 101.3 kPa was studied with the addition of 1-butyl-3-methylimidazolium hydrogen sulfate, 1-hexyl-3-methylimidazolium hydrogen sulfate and 1-butyl-3-methylimidazolium nitrate, respectively. The results showed that the volatility of TOX increased with the increase in IL dosage. And the volatility of water decreased with the increase in IL dosage. The relative volatility of TOX to H_(2)O was improved with the increase in ILs dosage. The azeotrope could be destroyed with an IL mole fraction of about 0.10. A non-random two-liquid(NRTL) model was successfully used to correlate the experimental data. The interaction parameters were obtained by fitting the experimental data with the model. The results indicated that a strong interaction existed between ILs and water. The strong interaction improved the volatility of TOX and inhibited the volatility of water, and then intensified the relative volatility of TOX to H_(2)O. The results showed that an ILs with strong polarity and hydrophilicity may be a potential additive to improve the TOX concentration in the equilibrated vapor phase.
