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Discussing the mechanisms of the pinacol coupling reactions catalyzed by bidentate and tetradentate chiral ligands.

四、分别对二齿手性配体和四齿手性配体催化Pinacol偶联反应机理进行了探讨。

The 91% ee value was obtained by the pinacol coupling reaction catalyzed by 15mol% Schiff-base prepared by the chiral 1, 2-Diphenyethylenediamine and 2-pyridinecarboxaldehyde.

2由手性1，2-二苯基二胺与两分子2-吡啶醛缩合的Schiff-Base催化的Pinacol偶联反应，仅用15mmol％的量，可取得91％的ee值，这是不对称Pinacol偶联反应最好的结果之一。

We screened a set of Lewis base organocatalysts derived from chiral pipecolinic acid and tert-butanesulfinamide for the reduction of-N-Cbz-1- phenylpropenamine, including newly designed ones and some of those previously developed in our lab. However, only moderate stereoselectivities, albeit high yields were obtained.

在本课题组前期研究的基础上，我们筛选并设计了一系列以手性哌啶酸和叔丁基亚磺酰胺为母体的有机小分子路易斯碱催化剂，它们能催化三氯氢硅对-N-苄氧羰基-1-苯基丙烯胺的不对称还原，获得很高的收率和中等的对映选择性，并且具有很好的底物普适性。

Starting from chiral proline, pipecolinic acid, piperazine-2-carboxylic acid and 1,2-diphenyl amino alcohol, a series of structurally simple and easily prepared amides were developed as highly effective Lewis basic organocatalysts for the asymmetric reduction of imines with trichlorosilane as the reducing agent, which promoted the reduction of N-aryl imines with high yields and excellent enantioselectivities with an unprecedented substrate spectrum.

本文分别由手性脯氨酸、哌啶酸、哌嗪酸以及氨基醇出发，设计和合成了一系列结构新颖、合成简便、性能优良的酰胺类有机小分子路易斯碱催化剂，以廉价的三氯氢硅为氢源，用这些催化剂催化亚胺不对称还原，得到了非常优良的收率、对映选择性和前所未有的底物普适性。

Addition of metallated terminal alkynes to carbonyls is considered as an effective route for the synthesis of chiral propargyl alcohols and has gained considerable significance in recent years.

末端炔对羰基化合物的不对称加成反应是构建手性炔丙醇的重要方法之一，其产生的光学活性炔丙醇是很多天然产物，精细化学品及药物分子的重要合成砌块。

Chiral propargylic alcohols present in many bioactive natural products.These building blocks are also important pharmaceutical intermediates.

手性炔丙醇结构存在于许多具有生物活性的天然产物中，并且也是许多手性药物的重要合成前体。

The asymmetric alkynylation of carbonyls is proved to be one of the most powerful procedures for organic synthetic chemistry,where the formation of one carbon-carbon bond and one chiral center of propargylic alcohol can be achieved in one step,and has attracted organic chemists\' most attentions.Plenty of works have been reported in recent years.

由于催化末端炔对羰基化合物的不对称加成在制备手性炔丙醇的同时，能够构建一个碳碳键和一个手性中心，因而该领域的研究受到了研究者的广泛关注，有大量的研究工作见报道。

Optically active propargylic alcohols are very useful and important precursors to many chiral organic compounds including natural products, pharmaceutical compounds and macromolecules.

手性丙炔醇是非常重要的合成中间体，广泛应用于天然产物、药物以及复杂大分子化合物等的合成。

The thesis consists of two main sections. The synthesis of 1,3,4-thiadiazoles,triazolotriazines and dioxapyrrolinopyrazoles containing chiral pyrazolyl moietyfrom D-glucose is described in the first part and the section one is about theDiels-Alder reactions between dienophile enaminones and diene 1,2,4-triazines,which provides a new methodology to construct the pyridine compounds. A total of37 new compounds were synthesized.

本论文包含两部分内容，一是以D-葡萄糖为原料合成含手性吡唑基的1，3，4-噁二唑、三唑并三嗪及二氧代吡咯啉并吡唑类化合物；二是将烯胺酮作为亲双烯体，与双烯体1，2，4-三嗪类化合物发生Diels-Alder反应，发现了一令人意外的构建吡啶类化合物的新方法。

In the third chapter, the synthesis of5-[(1"S)-1",2"-diacetyl-oxyethyl]-1-phenylpyrazol-3-carboxaldehyde oxime(2) from5-[(1"S)-1",2"-diacetyl-oxyethyl]-1-phenylpyrazol-3-carboxaldehyde(1) and phenyl-hydrazine were introduced firstly. The synthesis of nine dioxapyrrolino[3,4-c]pyrazoles containing chiral pyrazolyl moiety(6a-i) from 2 with N-substituted-phenylmaleimide by nonmetal oxidant IBD-initiated intermolecular 1,3-dipolarcycloaddition was described in detail.

第三章首先以5-[(1′S)-1′，2′-二乙酰氧基乙基]-1-苯基吡唑-3-醛(1)和苯肼为原料，合成了化合物5-(1′S)-1′，2′-二乙酰氧基乙基1-1-苯基吡唑-3-醛-苯腙(2)；再用化合物(2)与N-取代苯基马来酰亚胺反应，利用无金属氧化剂—IBD引发1，3-偶极反应，发生分子间的环加成，合成了9种新型手性吡唑连二氧代吡咯啉并

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％。