查询词典 chiral

Chiral amino-hydroxy compounds have been proved to be a very efficient class of ligands in a variety of catalytic asymmetric syntheses and chiral auxiliary synthesis catalyzed by metallic ions.

手性氨基-羟基化合物是一类用于催化不对称合成和手性辅助合成的重要配体。

Asymmetric autocatalysis intrinsically has the following advantages: chiral amplification of production, high reaction efficiency, easy purification of the product, consecutive reaction, and is a new aspect of chiral synthesis.

不对称自催化具有手性自动放大、反应活性较高、产物处理较易、反应体系连续等特点，是不对称化学的一个新的领域。

In this thesis, the emphasis is on the research of synthesis of a novel chiral imidazolium salt and application of chiral/achiral imidazolium salt in catalytic benzoin condensations.

本文致力于手性咪唑鎓盐离子液体的合成及手性/非手性咪哗基催化安息香缩合反应的研究。

In fact, the application of chiral ILs in asymmetric catalytic transformations is still at a preliminary stage.Benzoin is an important intermediate in organosynthesis. And more than, chiral benzoin is important structure unit of many bioactive compounds and building blocks of many enantioselective synthesis.

苯偶姻是一种重要的有机合成中间体，而且光学活性苯偶姻是许多生物活性化合物的重要结构单元，是可用于立体选择性合成生物活性有机分子的重要合成砌块。

Design and synthesis of chiral phosphorus ligands and the applications of them in catalytic asymmetric reactions has been a hot topic. Researchers betake themselves to develop novel chiral phosphorus ligands to solve problems that the existing ones cannot do.

中文摘要手性膦配体的设计与合成及其在不对称催化中的应用一直是研究的热点领域，研究人员一直致力于开发新型的手性膦配体来解决已有配体不能解决的问题。

The reported organocatalyst for asymmetric Michael additions include proline and its derivatives, chiral imidazolidinone derivatives, chiral urea, cinchona alkaloids and so on.

目前报道的催化Michael加成反应的有机催化剂主要有脯氨酸及其衍生物、手性咪唑啉酮、手性脲、金鸡纳碱衍生物等。

Chiral nonracemic fluoro-organic molecules with a fluorine atom on a stereogenic center are readily prepared via chiral electrophilic fluorinating reagent-mediated enantioselective fluorinations, substrate-controlled enantioselective electrophilic fluorinations, chiral metal complexes and asymmetric catalyst—directed catalytic enantioselective fluorinations.

高光学活性的手性氟化物可通过手性亲电氟化试剂诱导的立体选择性氟化反应，基于底物的手性氟化反应以及手性催化剂诱导的不对称催化氟化反应等来制备。

This study demonstrates optically and spatially band-tunable color cone lasers based on DDCLC cells with a photoisomerizable chiral dopant. The band-tunability is attributable to the recovery of the helix of the CLC resulted from the trans-cis isomerization induced decrease of the helical twisting power of the chiral dopant.The more the chiral cis-isomers are produced, the larger the tuned lasing band is.

本文主要藉由在胆固醇液晶射中加入可光致同素构化亲手性材，使胆固醇液晶所输出的彩色锥角射波段可光调控及空间调控，其射输出波段可调控的机制是由於当同素构化反应产生后，光致同素构化亲手性材的HTP值低并造成胆固醇液晶距改变，藉此间接调控输出的射波长，同素构化的程愈高，胆固醇液晶所输出的彩色锥角射波段可调控范围也愈大。

Chiral ligands mentioned above and their complexes with acetate copper were used as enantio-selective catalysts in asymmetric cyclopropanation reactions of diazoacetate and 1,1-diphenyl ethylene. Investigations indicate that all of them reveal certain optical-selective capability, but chiral C2-symmetric 2,6-bispyridine ligands show better catalytic capability than chiral asymmetric schifF-base ligands.

选择了2个手性2，6-吡啶双噁唑啉配体和6个手性不对称席夫碱配体与醋酸铜形成的配合物作为催化剂，对重氮乙酸乙酯与1，1-二苯乙烯不对称环加成进行催化反应，发现这8个催化剂对1，1-二苯乙烯的不对称环丙烷化反应都表现出了一定的光学活性诱导能力，手性2，6-吡啶双噁唑啉-铜类具有比手性Schiff碱-铜类更好的催化性能。

The X-ray analysis of the chiral macrocycle Ⅲb shows that the chiral ligand with acavity is rather rigid and strained. The unsymmetrical spatial structure of Ⅲb wellexplains the different recognition to chiral small molecules.

结果表明大环Ⅲb是具有一定大小空腔的扭曲型刚性分子，这种环系的不对称空间结构能够很好地解释它对手性小分子的不同识别作用。

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。