共查询到20条相似文献,搜索用时 15 毫秒
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Juanjo Cabezas-Giménez Dr. Vanesa Lillo Dr. José Luis Núñez-Rico Dr. M. Nieves Corella-Ochoa Dr. Jesús Jover Prof. Dr. José Ramón Galán-Mascarós Prof. Dr. Anton Vidal-Ferran 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(68):16956-16965
TAMOF-1 , a homochiral metal-organic framework (MOF) constructed from an amino acid derivative and Cu(II), was investigated as a heterogeneous catalyst in kinetic resolutions involving the ring opening of styrene oxide with a set of anilines. The branched products generated from the ring opening of styrene oxide with anilines and the unreacted epoxide were obtained with moderately high enantiomeric excesses. The linear product arising from the attack on the non-benzylic position of styrene oxide underwent a second kinetic resolution by reacting with the epoxide, resulting in an amplification of its final enantiomeric excess and a concomitant formation of an array of isomeric aminodiols. Computational studies confirmed the experimental results, providing a deep understanding of the whole process involving the two successive kinetic resolutions. Furthermore, TAMOF-1 activity was conserved after several catalytic cycles. The ring opening of a meso-epoxide with aniline catalyzed by TAMOF-1 was also studied and moderate enantioselectivities were obtained. 相似文献
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Scott E. Denmark Prof. Dr. Thomas Vogler Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(43):11737-11745
Enantiomerically enriched thiiranium ion 5 has been prepared by silver‐assisted ionization of chloro sulfide 4 at ?20 °C. This thiiranium ion is configurationally stable in solution up to room temperature as demonstrated by the stereospecific capture of the ion by various oxygen‐ and nitrogen‐based nucleophiles. Both isolated olefins and weak Lewis bases can promote the racemization of 5 but these processes can also be suppressed at low temperature. Capture of 5 by methanol is faster than the racemization processes. 相似文献
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酰胺型手性固定相反相拆分布洛芬药物对映体 总被引:5,自引:0,他引:5
利用酰胺型手性固定相反相拆分了布洛芬对映异构体,用有0.01mol/L NH4Ac的甲醇和水作流动相。在优化分离条件的同时,研究了不同的有机调节和对分离的影响,并探讨了分离的机理。 相似文献
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Satoshi Horino Tomoya Nishio Shinji Kawanishi Shinya Oki Koichi Nishihara Dr. Takashi Ikawa Dr. Kyohei Kanomata Karla Wagner Prof. Dr. Harald Gröger Prof. Dr. Shuji Akai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(60):e202202437
Natural lipases typically recognize enantiomers of alcohols based on the size differences of substituents near the carbinol moiety and selectively react with the R enantiomers of secondary alcohols. Therefore, lipase-catalyzed dynamic kinetic resolution (DKR) of racemic secondary alcohols produces only R enantiomers. We report herein a method for obtaining S enantiomers by DKR of secondary 3-(trialkylsilyl)propargyl alcohols by using a well-known R-selective Pseudomonas fluorescens lipase in combination with a racemization catalyst VMPS4, in which the silyl group reverses the size relationship of substituents near the carbinol moiety. We have already reported R-selective DKR of the corresponding propargyl alcohols without substituents on the ethynyl terminal carbon, and the presence of an easily removable silyl group has enabled us to produce both enantiomers of propargyl alcohols in high chemical yields and with high enantiomeric excess. In addition, immobilization of the lipase on Celite was found to be important for achieving a high efficiency of the DKR. 相似文献
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利用手性Chiralcel OD柱高效液相色谱对一系列苯丙氨酸酯类衍生物对映异构体进行了拆分,获得了良好的分离结果。讨论了化合物的结构对拆分效果的影响。 相似文献
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高玉玲 《理化检验(化学分册)》2012,(11):1324-1325,1330
采用加压毛细管电色谱法,以羟丙基-β-环糊精作为手性选择剂,对盐酸奥昔布宁对映体进行手性分离。在优化的试验条件下,16g·L-1羟丙基-β-环糊精为手性选择剂,pH 2.8的乙腈-5mmol·L-1磷酸盐缓冲溶液以体积比60比40混合溶液为流动相,运行电压18kV,毛细管柱温度18℃,盐酸奥昔布宁对映体在14min内成功分离。 相似文献
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Lisa K. Thalén Dongbo Zhao Dr. Jean‐Baptiste Sortais Dr. Jens Paetzold Dr. Christine Hoben Dr. Jan‐E. Bäckvall Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(14):3403-3410
Dynamic transformation : A racemization catalyst and the enzyme Candida antarctica lipase B (CALB) were combined in a one‐pot dynamic kinetic resolution (DKR) of primary amines, which were transformed to their corresponding amides in up to 95 % yield and >99 % ee. This chemoenzymatic DKR was also applied to the synthesis of norsertraline (see scheme).
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以L-苯丙氨酸-铜(Ⅱ)络合物作为流动相的手性添加剂,提出了高精氨酸对映体的高效液相色谱拆分方法。选用Waters Atlantis C_(18)色谱柱,流动相为pH 2.8的含0.71mmol·L~(-1)L-苯丙氨酸-0.351mmol·L~(-1)硫酸铜的甲醇-水(20+80)溶液,紫外检测波长为200nm,进样量20μL,流量为0.5 mL·min~(-1)时,高精氨酸对映体得到良好的分离,分离度达到1.8。L-高精氨酸和D-高精氨酸的峰面积与其质量浓度分别在2.00~72.05mg·L~(-1)和3.00~60.23mg·L~(-1)范围内呈线性关系,检出限(3S/N)分别达到1.0mg·L~(-1)和1.5mg·L~(-1)。 相似文献