The atom transfer radical polymerization(ATRP) of (-)-menthyl methacrylate((-)-MnMA) mediated by CuCl/bipyridine and ethyl 2-bromopropionate or 1-phenylethyl bromide in THF system has been studied. The dependence of ...The atom transfer radical polymerization(ATRP) of (-)-menthyl methacrylate((-)-MnMA) mediated by CuCl/bipyridine and ethyl 2-bromopropionate or 1-phenylethyl bromide in THF system has been studied. The dependence of the specific rotation on molecular weight and the CD of Poly((-)-MnMA) thus obtained was investigated.展开更多
In this paper, (-)menthyl methacrylate((-)MnMA) was polymerized at 78C in toluene with three types of anionic catalysts, which were complexes of fluorenyllithium with (-)sparteine - ((-)-Sp) , (S, S)-(+)-2, 3-dimethox...In this paper, (-)menthyl methacrylate((-)MnMA) was polymerized at 78C in toluene with three types of anionic catalysts, which were complexes of fluorenyllithium with (-)sparteine - ((-)-Sp) , (S, S)-(+)-2, 3-dimethoxy-1, 4-bis(dimethylamino)butane((+)DDB) and N,N,N,N-tetra- methylethylenediamine(TMEDA), and the chiral optical property of the obtained polymer was studied. The circular dichroism (CD) spectrum of the polymer showed negative Cotton effect.展开更多
The reverse atom transfer radical polymerization(RATRP) of (-)-menthyl methacrylate ((-)-MnMA) with AIBN(AIBN/CuCl2/bipyridine(bipy) or (-)sparteine((-)Sp) =1/2/4) initiating system in THF has been studied. The depen...The reverse atom transfer radical polymerization(RATRP) of (-)-menthyl methacrylate ((-)-MnMA) with AIBN(AIBN/CuCl2/bipyridine(bipy) or (-)sparteine((-)Sp) =1/2/4) initiating system in THF has been studied. The dependence of the specific rotation on molecular weight was investigated.展开更多
Cationic ring-opening copolymerization of 1, 4-anhydro-2, 3-O-isopropylidene-α-D-ribo-pyranose (AIRP) with 1,4-anhydro-2,3-di-O-benzyl-α-D-ribopyranose (ADBR) preparedfrom D-ribose was studied. Copolymerization usin...Cationic ring-opening copolymerization of 1, 4-anhydro-2, 3-O-isopropylidene-α-D-ribo-pyranose (AIRP) with 1,4-anhydro-2,3-di-O-benzyl-α-D-ribopyranose (ADBR) preparedfrom D-ribose was studied. Copolymerization using SbCl_5 or BF_3 OEt_2 as catalyst atlow temperature gave stereoregular (1→4)β-D-ribofuranan (C-1 and C-4 ring cleavagesee Scheme 1) or (1→5) α-D-ribofuranan (C-1 and C-5 ring cleavage) respectively. Theeffects of catalysts, reaction time and temperatures on yield and stereoregularity of the ob-tained polymers were studied. Polymers were characterized by molecular weight, ~1HNMR,^(13)CNMR and optical rotation.展开更多
The changes of the specific rotation and sign of optically active BINOL have been studied in polar/non polar solvents and at the different pH values of solvent. It is considered that these changes are determined by t...The changes of the specific rotation and sign of optically active BINOL have been studied in polar/non polar solvents and at the different pH values of solvent. It is considered that these changes are determined by the equilibrium studies between cisoid and transoid conformations of BINOL with the same configuration ( R or S ) which related to the change of the dihedral angle between two naphthalene ring planes of BINOL.展开更多
文摘The atom transfer radical polymerization(ATRP) of (-)-menthyl methacrylate((-)-MnMA) mediated by CuCl/bipyridine and ethyl 2-bromopropionate or 1-phenylethyl bromide in THF system has been studied. The dependence of the specific rotation on molecular weight and the CD of Poly((-)-MnMA) thus obtained was investigated.
基金the National Natural Science Foundation of China for financial support
文摘In this paper, (-)menthyl methacrylate((-)MnMA) was polymerized at 78C in toluene with three types of anionic catalysts, which were complexes of fluorenyllithium with (-)sparteine - ((-)-Sp) , (S, S)-(+)-2, 3-dimethoxy-1, 4-bis(dimethylamino)butane((+)DDB) and N,N,N,N-tetra- methylethylenediamine(TMEDA), and the chiral optical property of the obtained polymer was studied. The circular dichroism (CD) spectrum of the polymer showed negative Cotton effect.
文摘The reverse atom transfer radical polymerization(RATRP) of (-)-menthyl methacrylate ((-)-MnMA) with AIBN(AIBN/CuCl2/bipyridine(bipy) or (-)sparteine((-)Sp) =1/2/4) initiating system in THF has been studied. The dependence of the specific rotation on molecular weight was investigated.
文摘Cationic ring-opening copolymerization of 1, 4-anhydro-2, 3-O-isopropylidene-α-D-ribo-pyranose (AIRP) with 1,4-anhydro-2,3-di-O-benzyl-α-D-ribopyranose (ADBR) preparedfrom D-ribose was studied. Copolymerization using SbCl_5 or BF_3 OEt_2 as catalyst atlow temperature gave stereoregular (1→4)β-D-ribofuranan (C-1 and C-4 ring cleavagesee Scheme 1) or (1→5) α-D-ribofuranan (C-1 and C-5 ring cleavage) respectively. Theeffects of catalysts, reaction time and temperatures on yield and stereoregularity of the ob-tained polymers were studied. Polymers were characterized by molecular weight, ~1HNMR,^(13)CNMR and optical rotation.
基金ProjectsupportedbytheNationalNaturalScienceFoundationofChina (No .2 99740 3 4)
文摘The changes of the specific rotation and sign of optically active BINOL have been studied in polar/non polar solvents and at the different pH values of solvent. It is considered that these changes are determined by the equilibrium studies between cisoid and transoid conformations of BINOL with the same configuration ( R or S ) which related to the change of the dihedral angle between two naphthalene ring planes of BINOL.
