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The progress in synthesis of chiral mandelic acid and resolution of racemic mandelic acid are reviewed.

综述了手性扁桃酸的合成及外消旋扁桃酸拆分的研究进展。

The asymmetric synthesis of mandelic acid in the presence of a chiral phase transfer catalyst was also studied.

本文研究了由苯甲醛和卤仿在相转移催化条件下合成扁桃酸的工艺，探讨了反应条件，特别是相转移催化剂的种类对反应的影响。

Firstly, a series of organic molecules which use phthalimido group as electron acceptor, N as electron donor, COO~- as eletrofugal group were synthesized based on SET-promoted photocyclization processes. These compounds were irradiated by 500 W ultraviolet under nitrogen atmosphere in room temperature. After filtration of the photochemical character of these molecules, substrate S1 and S2 were selected as appropriate model reactants. Secondly, the monosubstituted derivatives at the 6-position ofβ-cyclodextrin were synthesized as chiral template of photocyclization.

首先，以单电子转移机理为指导，设计了一系列以邻苯二甲酰亚胺基为电子受体、N为电子给体、羧基为离去基团的光环合反应底物，这些化合物在氮气保护下以500瓦紫外光室温下进行光照反应，对这一系列的分子的反应情况进行了研究与筛选，最终选择底物S1和S2作为研究光环合反应中立体控制方法的模型底物；其次，又合成了一系列6-位单取代β-环糊精，以此作为光环合反应的手性模板。

The yields were 67～89% and 61～90% respectively, and the ees were 66～99. 9% and 68～99. 9% respectively (except for trans-5-decene and ally naphthyl ether). With trans-stilbene as the substrate, chiral ligands and OsO〓 could be recovered and reused five times in the AD reaction with high catalytic activity and stereoselectivity.

4在PF〓/NMO体系中，将配体8和10分别用于八种烯烃的AD反应，配体、OsO〓和底物的摩尔比为0.02/0.015/1时，化学产率分别为67～91％和61～90％，ee值分别为66～99.9％和68～99.9％（反式-5-癸烯和萘基烯丙基醚除外）。

In this paper, the enantioseparation of naringenin was firstly studied by using CDMPC chiral stationary phase.

首次在纤维素三(3，5二甲苯基氨基甲酸酯)手性固定相上，对柚皮素进行了对映体分离研究。

The aromatic position isomers, such as xylene and nitrotoluene, were separated well. Moreover, some chiral compounds including alcohol, amine, ester etc., were also resolved.

不但对二甲笨、硝甲苯等难分离的芳香族位置异构体，而且对醇、胺、酯等多种类型的手性异构体均有很好的分离能力和手性选择能力。

In contrast, the Schiff bases without long alkyl chain could not form supramolecular chiral assemblies in organogel.

表明通过凝胶的形成，胶凝剂的手性能传递到带有长链的席夫碱上。

Recent advances in the application of chiral nitrogen-containing ligands in asymmetric addition reactions to imines with organolithium reagents are reviewed.

综述了近10余年来手性含氮配体在有机锂试剂对亚胺不对称加成反应中应用的研究进展。

The possibility of 1,4-asymmetric induction in some nucleophilic addition reactions of chiralγ-amino Z-enals 7 with organolithium compounds was investigated.

本文研究了在手性的顺式-γ-氨基-α，β-不饱和醛(7)与有机锂化合物的亲核加成反应中的1，4-不对称诱导效应。

The recent advancement of the asymmetric addition of organozinc reagent s to ketones and α-ketoesters is reviewed according to the type of the chiral ligands, with an emphasis on the introduction of the ligands with high efficiency and high selectivity.

按照手性配体的结构类型分类，综述了近年来有机锌试剂对酮、α-酮酯等化合物的不对称加成反应的研究进展，对高效、高选择性的手性配体在该类反应中的应用进行了重点评述。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。