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1-膦酸二乙酯-D-核糖的端头异构体的合成
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作者 陈娟 Gregory Linn +1 位作者 王晓磊 闻建平 《精细化工》 EI CAS CSCD 北大核心 2006年第2期157-160,共4页
以D-核糖为起始原料,用两种不同的方法保护羟基,通过W adsworth-Emmons反应合成1-膦酸二乙酯-D-核糖的α、β端头异构体,以达到优化其合成分离方法的目的。方法A用2,3-O-异丙叉基-5-O-三甲基乙酰基-D-呋喃核糖与四乙基亚甲基二膦酸酯(TE... 以D-核糖为起始原料,用两种不同的方法保护羟基,通过W adsworth-Emmons反应合成1-膦酸二乙酯-D-核糖的α、β端头异构体,以达到优化其合成分离方法的目的。方法A用2,3-O-异丙叉基-5-O-三甲基乙酰基-D-呋喃核糖与四乙基亚甲基二膦酸酯(TEMDP)反应,得到2,3-O-异丙叉基-5-O-三甲基乙酰基-1-亚甲基膦酸二乙酯-D-呋喃核糖,然后用乙醇钠脱去酰基保护基。此时,分离端头异构物,总收率为81%。而后再将α、β分别在酸性条件下水解,得到目的产品,收率分别为94%和91%。方法B则是用2,3,5-O-三苄基-D-呋喃核糖通过W adsworth-Emmons反应形成膦酯糖,分离端头异构体,总收率为70%。然后分别用Pd/C在H2氛条件下还原得目的产物,产率分别为93%和91%。产物用1HNMR表征,证明合成方法可行。 展开更多
关键词 天然磷酸酯 1-膦酯糖 wadsworth-emmons反应 四乙基亚甲基二膦酸酯
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Synthesis, Photophysical Properties of Tribranched Chromophores Based on 1,3,5-Triazine Core and Different Electro-donating End-groups
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作者 刘莉 黄维 +3 位作者 史界平 吕昌贵 崔一平 陆国元 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第10期2129-2133,共5页
Three two-photon absorption (TPA) tribranched chromophores were successfully prepared, in which 1,3,5-triazine is been as electron deficient core, 1,4-phenylenedivinylene as conjugated bridge, 3,4-ethylenedioxy- thi... Three two-photon absorption (TPA) tribranched chromophores were successfully prepared, in which 1,3,5-triazine is been as electron deficient core, 1,4-phenylenedivinylene as conjugated bridge, 3,4-ethylenedioxy- thiophene (EDOT) (T1), N-methylpyrrole (T2) or triphenylamine (T3) as electron-donating end-groups. Their pho- tophysical properties were studied by absorption, one- and two-photon fluorescence and TPA cross-section deter- mination. The nonlinear transmission (NLT) measurement in femtoseconds (fs) regime at 800 nm indicates that TPA cross-section σ2 values of T1, T2 and T3 with extended π-conjugated bridge are much larger than the corresponding chromophore T4 with a short length bridge, and TPA cross-section of T1 with end-groups EDOT exhibits a remarkable enhancement compared with T2 and T3 having the same length It-system. The chromophores T1, T2 and T3 show also remarkable up-converted luminescence and optical limiting activity. 展开更多
关键词 chromophore TRIAZINE 3 4-ethylenedioxythiophene two-photon absorption PHOTOPHYSICS Homer- wadsworth-emmons reaction
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