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Recent advances in addition,reduction,and asymmetric reactions of imines were reviewed.

亚胺是一类羰基化合物与氨的缩合产物，作者综述了近年国内外亚胺在加成、还原和不对称反应等方面的研究进展

This review covers the recent advances on the asymmetric addition reactions of alkylzinc reagents with imines .

综述了烷基锌与亚胺不对称加成反应的最新进展。

The chiral ligands la-lf were used in the copper catalyzed asymmetric addition of diethylzinc to imines.

第二部分探索了一个新的含氮杂环丙烷的手性膦配体2的合成方法。

Chiral amines widely existed and play an important role in the nature. Catalytic asymmetric reduction of imines represents one of the most important methods for preparing chiral amines.

摘 要：手性胺化合物广泛存在于自然界中并扮演着重要的角色，亚胺的不对称催化还原反应是制备手性胺化合物的最直接有效的方法。

In the fifth part, asymmetric synthesis of β,γ-trans-alkenyl α-amino esters was achieved by chiral phosphoric acid catalyzed transfer hydrogenation of β,γ-alkynyl α-imino esters. Utilizing Hantzsch ester as the hydrogen donor, both the alkyne and imine moieties of β,γ-alkynyl α-imino esters were reduced to yield β,γ-trans-alkenyl α-amino esters with up to 96% ee.

第五部分工作中，使用手性磷酸作为催化剂，Hantzsch酯作为氢源，β，γ-炔烃取代的α-酮酸酯亚胺中的炔键和亚胺官能团均被还原，以中等的收率和优秀的对映选择性（up to 96% ee）得到β，γ-反式烯烃取代的α-氨基酸衍生物。

The number of optical isomers is 2n, where n is the number of asymmetric centers.

光学异构体的数量是2 n，在此n是不对称中心的数量。

Finally,we study meson mixing in asymmetric nuclear matter with spontaneous breaking of isospin symmetry in the framework of two flavor NJL model.

最后，我们在两味NJL模型的框架下研究了非对称核物质体系在同位旋对称性自发破缺时的介子混合现象。

Asymmetric reduction of prochiral ketone to these chiral alcohol s by active microbe cells is one of the most promising routes.

以4-氯苯乙酮为苯环上含卤素的芳香酮的模型底物，研究了活性酵母细胞在水相体系中催化该类芳香酮不对称还原合成相应手性醇的反应特性。

The asymmetric reduction of prochiral P-oxo ester, aromatic ketone and aliphatic ketone to its corresponding chiral alcohol by yeast cells were studied respectively in this work when ethyl 4-chloro-3-oxobutyrate, acetophenone and 2-octanone were as the model substrates.

本文以4-氯乙酰乙酸乙酯、苯乙酮和2-辛酮分别为β-羰基酯、芳香酮和脂肪酮的模型底物，研究了利用活性酵母细胞催化这三类前手性酮不对称还原合成相应手性醇的反应特性。

This method had been applied to determination of the optical purity of the asymmetric reduction products of prochiral ketones.

拆分方法已应用于潜手性酮不对称还原产物的光学纯度的鉴定，并取得了很好的效果。

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性，但我大喊，并在他们的方向扔石头让他们过的线索，远离我，以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。