查询词典 disubstituted

Previously, we reported chiral 2, 5-disubstituted pyrrolidine derivatives as chiral catalyst ligands in the reaction of diethylzinc with arylaldehydes. Very high yields and enationselectivities have been achieved in this asymmetric addition reaction.

我们小组以前合成的具有C〓-对称性的五员氮杂环类手性配体在二乙基锌和醛的不对称加成反应中取得了优良的结果。

A series of disubstituted monoamide s extractants were synthesized and their extracted species with uranyl nitrate were obtained by extraction method.

合成了系列双取代单酰胺萃取剂，利用萃取方法获得了与硝酸铀酰的萃合物。

The present invention relates to sulphonyloxazolamines of general formula, wherein R, R represent independently from each other H, A,-(CH2)n-Ar or alkenyl with 2-6 C atoms, R and R together also represent a mononuclear saturated heterocycle with 1-2 N, O and/or S atoms, Z is H, A, CF3, NO2, Hal, OH, OA, NH2, NHA or NA2, A represents alkyl with 1-6 C atoms, Ar is Z-monosubstituted or Z-disubstituted phenyl, halogen is F, Cl, Br or I, n is 1 or 2 or the physiologically acceptable salts or solvates thereof.

本发明涉及式磺酰基∴唑胺或其生理上可接受的盐或溶剂化物，其中R 1 ，R 2 每一个相互独立为H、A、－(CH 2 )n－Ar或具有2到6个C原子的链烯基，R 1 和R 2 也一起为具有1到2个N、O和/或S原子的单核饱和杂环，Z为H、A、CF 3 、NO 2 、卤素、OH、OA、NH 2 。NHA或NA 2 ，A为具有1到6个C原子的烷基，Ar为被Z取代的或Z二－取代的苯基，卤素为F、Cl、Br或I，n为1或2。

N,N′-Disubstituted ureas,used as intermediates for synthesis of pesticides,resin precursors and carbamates,were synthesized from carbon dioxide and primary amines(namely n-propylamine,n-butylamine,n-amylamine,n-hexylamine,benzylamine and aniline) over organic base catalysts.

以有机碱为催化剂，CO2与伯胺反应合成了N，N′-二取代脲；考察了有机碱种类、伯胺碳链长度、反应温度、CO2压力、反应时间、催化剂用量对合成反应的影响。

N,N′-Disubstituted ureas,used as intermediates for synthesis of pesticides,resin precursors and carbamates,were synthesized from carbon dioxide and primary amines(namely n-propylamine, n-butylamine ,n-amylamine,n-hexylamine,benzylamine and aniline) over organic base catalysts.

以正丁胺为反应基质、TBD为催化剂，合成N，N′-二丁脲的最佳反应条件为：反应温度180℃，CO2压力10.0M Pa，反应时间10h，TBD摩尔分数5.0%；在此条件下，N，N′-二丁脲的收率为81.8%；红外光谱表征结果表明，合成的产物为N，N′-二丁脲。

The new reaction of disubstituted phosphinosilane would be available in many organic syntheses.

这类新型反应为二取代膦基硅烷类化合物的研究开辟了新方向。

The key problem is to synthesize high stereoselectively trans- 2,5- disubstituted tetrahydrofurans.

高立体选择性合成反式-2，5-二取代四氢呋喃是期待解决的关键问题。

Reaction conditions, either the monosubstituted product (2) or the disubstituted product 3

出特定的反应条件，学生将会确定主产物究竟是橙色的乙醯二茂铁(2)呢还是红色的

The positive charge transport properties of monosubstituted triphenylene are better than those of disubstituted and trisubstituted triphenylenes obviously.

在苯并菲上单取代的分子明显比其双取代、三取代的分子正电荷传输性质好。

However, if this reaction was carried out at low temperature, methoxy groups monosubstituted and disubstituted complexes 14a and 13a were isolated as major products, and only a little of carborane cage opened complexes were obtained.

而在低温下反应，得到的是甲氧基单取代的产物14a和双取代的13a，以及少量的开笼产物。

In the United States, chronic alcoholism and hepatitis C are the most common ones.

在美国，慢性酒精中毒，肝炎是最常见的。

If you have any questions, you can contact me anytime.

如果有任何问题，你可以随时联系我。