Five chiral stationary phases (CSPs) were used to separate the enantiomers of a series of O,O-diethyl (p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates. A chiral recognition mechanism was presented to expl...Five chiral stationary phases (CSPs) were used to separate the enantiomers of a series of O,O-diethyl (p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates. A chiral recognition mechanism was presented to explain the resolution of these compounds. Results show that CSP with strong π-acceptor 3,5-dinitrobenzoyl group and high steric hindrance has the best resolution ability in chiral separation of O,O-diethyl (p-methylbenzenesulfonamindo)-aryl(alkyl)-methylphosphonates. When a CSP has just a strong π-acceptor 3,5-dinitrobenzoyl or high steric hindrance it does not have good chiral resolution ability. The chiral recognition is more difficult when the CSP has more than one asymmetric center.展开更多
Two chiral selectors were synthesized from tartaric acid. The selectors were simultaneously immobilized on 3-aminopropyl silica gel to obtain a new biselector chiral stationary phase (CSP) in order to determine the ...Two chiral selectors were synthesized from tartaric acid. The selectors were simultaneously immobilized on 3-aminopropyl silica gel to obtain a new biselector chiral stationary phase (CSP) in order to determine the influence of selector structure of biselector CSPs on the chiral recognition capability. For comparison, the single-selector CSP was also prepared. The biselector CSP shows an improved overall chiral recognition capability in comparison with the single-selector CSP. During the enantioseparation, temporary diastereoisomers are likely formed by complexation between a chiral analyte and the two selectors on the biselector CSP. The functional groups in the two selectors are complementary in electronic effect and/or in steric hindrance for the chiral recognition.展开更多
A partially substituted β-cyclodextrin chiral stationary phase was prepared by the reaction of phenyl isocyanate. The enantiomers of a series of O,O-diethyl(p-methylbenzenesulfonamido)-aryl(or alkyl)-methylphos-. pho...A partially substituted β-cyclodextrin chiral stationary phase was prepared by the reaction of phenyl isocyanate. The enantiomers of a series of O,O-diethyl(p-methylbenzenesulfonamido)-aryl(or alkyl)-methylphos-. phonates were studied on the prepared phenyl carbamate derivative β-cyclodextrin bonded phase and a commercial ( S)-(.+ )-l-(l-naphthyl)ethylcarbamate derivative β-cyclodextrin bonded phase on normal phase chromato-graphic condition. Results show that the prepared phenyl carbamate derivative β-cyclodextrin bonded phase has better enantiomeric selectivity to the series of compounds. A chiral recognition mechanism was suggested for the separation of these novel organic phosphorus enantiomers.展开更多
基金Project supported by the National Natural Science Foundation of China.
文摘Five chiral stationary phases (CSPs) were used to separate the enantiomers of a series of O,O-diethyl (p-methyl-benzenesulfonamindo)-aryl(alkyl)-methylphosphonates. A chiral recognition mechanism was presented to explain the resolution of these compounds. Results show that CSP with strong π-acceptor 3,5-dinitrobenzoyl group and high steric hindrance has the best resolution ability in chiral separation of O,O-diethyl (p-methylbenzenesulfonamindo)-aryl(alkyl)-methylphosphonates. When a CSP has just a strong π-acceptor 3,5-dinitrobenzoyl or high steric hindrance it does not have good chiral resolution ability. The chiral recognition is more difficult when the CSP has more than one asymmetric center.
基金Supported by the National Natural Science Foundation of China (20675061 and 50973086)the Research Project of Department of Education of Hubei Province (Z20081501)
文摘Two chiral selectors were synthesized from tartaric acid. The selectors were simultaneously immobilized on 3-aminopropyl silica gel to obtain a new biselector chiral stationary phase (CSP) in order to determine the influence of selector structure of biselector CSPs on the chiral recognition capability. For comparison, the single-selector CSP was also prepared. The biselector CSP shows an improved overall chiral recognition capability in comparison with the single-selector CSP. During the enantioseparation, temporary diastereoisomers are likely formed by complexation between a chiral analyte and the two selectors on the biselector CSP. The functional groups in the two selectors are complementary in electronic effect and/or in steric hindrance for the chiral recognition.
基金Project (No. 98010) supported by the 11th Foundation of State Key Laboratory of Elemento-Organic Chemistry,Nankai University.
文摘A partially substituted β-cyclodextrin chiral stationary phase was prepared by the reaction of phenyl isocyanate. The enantiomers of a series of O,O-diethyl(p-methylbenzenesulfonamido)-aryl(or alkyl)-methylphos-. phonates were studied on the prepared phenyl carbamate derivative β-cyclodextrin bonded phase and a commercial ( S)-(.+ )-l-(l-naphthyl)ethylcarbamate derivative β-cyclodextrin bonded phase on normal phase chromato-graphic condition. Results show that the prepared phenyl carbamate derivative β-cyclodextrin bonded phase has better enantiomeric selectivity to the series of compounds. A chiral recognition mechanism was suggested for the separation of these novel organic phosphorus enantiomers.