β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid de...β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives.展开更多
AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfo...AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfonic acid as a catalyzer, a series of hyperbranched poly(amide-ester) (HBPAE) were successfully synthesized from prepared AB2 monomer by solution condensation polymerization through "one-step process" or "pseudo one-step process" (using pentaerythritol as a center core). The processes were carried out at high temperature of 120 ℃ for 6 h in air atmosphere (inert protection free) with reduced pressure distillation (0.08--0.096 MPa). The results of FT-IR, UV-Vis, TGA, and intrinsic viscosity testing by Ubbelodhe viscometer showed that the prepared HBPAEs possess three-dimensional configuration with unsaturated conjugate structure, large numbers of branches and numerous terminal hydroxyl groups. These result in their low viscosity, high solubility and thermal stability.展开更多
基金the financial support form National Natural Science Foundation of China(No.20472116).
文摘β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives.
基金the National Science and Technology Support Project of "the Eleventh Five-year Plan"(2006BAE03B06-03)the New Century Talents Support Program of Chinese Education Department (NCET-04-0614)
文摘AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfonic acid as a catalyzer, a series of hyperbranched poly(amide-ester) (HBPAE) were successfully synthesized from prepared AB2 monomer by solution condensation polymerization through "one-step process" or "pseudo one-step process" (using pentaerythritol as a center core). The processes were carried out at high temperature of 120 ℃ for 6 h in air atmosphere (inert protection free) with reduced pressure distillation (0.08--0.096 MPa). The results of FT-IR, UV-Vis, TGA, and intrinsic viscosity testing by Ubbelodhe viscometer showed that the prepared HBPAEs possess three-dimensional configuration with unsaturated conjugate structure, large numbers of branches and numerous terminal hydroxyl groups. These result in their low viscosity, high solubility and thermal stability.