4-(2-Benzyloxyethoxycarbonyl)-2-oxetanone, an β-substituted-β-lactones with latent pendent hydroxyl groups,was synthesized from L-aspartic acid. Firstly, bromosuccinic acid was synthesized from L-aspartic acid and i...4-(2-Benzyloxyethoxycarbonyl)-2-oxetanone, an β-substituted-β-lactones with latent pendent hydroxyl groups,was synthesized from L-aspartic acid. Firstly, bromosuccinic acid was synthesized from L-aspartic acid and it was dehydrated to bromosuccinic anhydride by TFFA. Then the anhydride was alcoholysized to the monoester mixture by 2-benzyloxy ethanol. Finally, the novel monomer was got through a intromolecular cyclization of the mixture ester, and then it was further purified by silicon gel chromatogram. The product and the intermediates were characterized by {{}+1H NMR}, {}+{13}C NMR and elemental analysis. In addition, 2-benzyloxy ethanol was synthesized with a simplyified procedure and high yield by using Williamson method.展开更多
The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5-nitryl-6-hydroxybenzoxazole(MNB) in N2 atmosphere was studied by thermogravimetry(TG) and differential thermogravimetry(DTG).It is a sequential process.The mo...The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5-nitryl-6-hydroxybenzoxazole(MNB) in N2 atmosphere was studied by thermogravimetry(TG) and differential thermogravimetry(DTG).It is a sequential process.The molecular bond orders were calculated by GAMESS method and the IR spectra of MNB and its intermediates in thermal decomposition at various temperatures were determined.The mechanism of the thermal decomposition has been discussed,the C-N bond breakdown and the nitro group elimination occurred in the initial step of the decomposition.The thermal decomposition kinetic parameters such as apparent activation energy E=115.5kJ·mol-1,pre-exponential factor A = 1.698×1010 min-1 and apparent reaction order n = 0 were obtained according to test data.展开更多
文摘4-(2-Benzyloxyethoxycarbonyl)-2-oxetanone, an β-substituted-β-lactones with latent pendent hydroxyl groups,was synthesized from L-aspartic acid. Firstly, bromosuccinic acid was synthesized from L-aspartic acid and it was dehydrated to bromosuccinic anhydride by TFFA. Then the anhydride was alcoholysized to the monoester mixture by 2-benzyloxy ethanol. Finally, the novel monomer was got through a intromolecular cyclization of the mixture ester, and then it was further purified by silicon gel chromatogram. The product and the intermediates were characterized by {{}+1H NMR}, {}+{13}C NMR and elemental analysis. In addition, 2-benzyloxy ethanol was synthesized with a simplyified procedure and high yield by using Williamson method.
文摘The thermal decomposition of 2-(4-methoxycarbonylphenyl)-5-nitryl-6-hydroxybenzoxazole(MNB) in N2 atmosphere was studied by thermogravimetry(TG) and differential thermogravimetry(DTG).It is a sequential process.The molecular bond orders were calculated by GAMESS method and the IR spectra of MNB and its intermediates in thermal decomposition at various temperatures were determined.The mechanism of the thermal decomposition has been discussed,the C-N bond breakdown and the nitro group elimination occurred in the initial step of the decomposition.The thermal decomposition kinetic parameters such as apparent activation energy E=115.5kJ·mol-1,pre-exponential factor A = 1.698×1010 min-1 and apparent reaction order n = 0 were obtained according to test data.
