In order to explain the high activity of N-phosphoryl-α-amino acids, ab initio and MNDO calculations are performed to study the reaction pathway of the intermediate formation from N-dimethylphosphoryl-α-alanine (DMP...In order to explain the high activity of N-phosphoryl-α-amino acids, ab initio and MNDO calculations are performed to study the reaction pathway of the intermediate formation from N-dimethylphosphoryl-α-alanine (DMP-α-Ala) and the structures and energies involved in the reaction.展开更多
A new conformational carbon-carbon bond free radical initiator diethyl [2,3-di(ethoxycarbonyl)-2,3-di(p-nitrophenyl)] succinate (EMNPS) was synthesized and identified by elemental analysis, FAB-MS, IR and H-1 NMR spec...A new conformational carbon-carbon bond free radical initiator diethyl [2,3-di(ethoxycarbonyl)-2,3-di(p-nitrophenyl)] succinate (EMNPS) was synthesized and identified by elemental analysis, FAB-MS, IR and H-1 NMR spectroscopy. The analytical results of single crystal X-ray show the conformation of EMNPS tends to be a stagger gauche form, and torsion angle of the two gauche phenyls is smaller than 60 degrees. There is obvious elongation in central carbon-carbon bond length (0.161 nm). EMNPS can be decomposed into two relatively stable free radicals measured by ESR. By initiating bulk polymeriza-tion of methyl methacrylate (MMA), EMNPS shows the ability of controlling the molecular weight of polymers.展开更多
文摘In order to explain the high activity of N-phosphoryl-α-amino acids, ab initio and MNDO calculations are performed to study the reaction pathway of the intermediate formation from N-dimethylphosphoryl-α-alanine (DMP-α-Ala) and the structures and energies involved in the reaction.
文摘A new conformational carbon-carbon bond free radical initiator diethyl [2,3-di(ethoxycarbonyl)-2,3-di(p-nitrophenyl)] succinate (EMNPS) was synthesized and identified by elemental analysis, FAB-MS, IR and H-1 NMR spectroscopy. The analytical results of single crystal X-ray show the conformation of EMNPS tends to be a stagger gauche form, and torsion angle of the two gauche phenyls is smaller than 60 degrees. There is obvious elongation in central carbon-carbon bond length (0.161 nm). EMNPS can be decomposed into two relatively stable free radicals measured by ESR. By initiating bulk polymeriza-tion of methyl methacrylate (MMA), EMNPS shows the ability of controlling the molecular weight of polymers.
