查询词典 aldehydes

In order to examine the catalytic activity of the new catalysts, we have carried out the direct asymmetric Aldol reaction of tetrahydro-4H-thiopyran-4-one with aldehydes.

催化剂的基本结构单元如下：为了检验新型有机催化剂的催化活性，我们研究了硫代四氢吡喃酮和各种醛的直接不对称Aldol反应。

We transformed RMgBr into R-Ti derivatives with the production of byproduct MgBrO~(i-Pr at the same time, but we didn\'t need romove the Mg salt by centrifugation or chelating reagents, for bis[2-(N,N-dimethylamino)ethyl] ether could chelate with Mg atom and thereby reduced the Louis acidity of Mg salt, so we used R-Ti derivatives produced in situ to alkylate the aldehydes induced by BINOL-Ti complexes..

我们通过利用TiO~(i-Pr_4使格氏试剂转化成烷基钛，同时产生具有亲核加成促进作用的副产物MgBrO~(i-Pr，由于BDMAEE能与MgBrO~(i--Pr络合降低其路易酸活性，所以不需要离心或者借助络合试剂完全除去镁盐，而使用原位生成的烷基钛在BINOL-Ti诱导下对醛进行不对称加成。

SAA ligand Lh could induce asymmetric addition of terminal alkyne to aldehydes without using air-sensitive Ti4and expensive Zn2.with good result of high yield (up to 99%) and good enantioselectivities (up to 84%ee).

将SAA配体Lh应用于在无Ti_4和Zn_2的条件下促进端基炔对醛的不对称加成反应中，反应的收率普遍较高，最高达99%，对映体选择性高达84%ee。

A one-pot synthesis of indoles by a palladium-catalyzed annulation of ortho haloanilines and aldehydes is reported by the group of Zhu J.

一个锅合成吲哚的钯催化圆环邻haloanilines报道，由77醛朱 J查看。

We have had the extensive studies on theα-acetyl-α-carbamoyl ketene--acetals and its further applications, for example, their adols condensations with aldehydes giveα-alkenoyl-α-carbamoyl ketene--acetals which can be utilized as the 1,5-bielectronic five-carbon components to react with various binucleophlilic species in a [5+1] annulation.

我们小组在以前的工作中对α-乙酰基-α-胺甲酰基二硫缩烯酮在合成中的应用进行了深入的研究，如与醛缩合生成α-烯酰基-α-胺甲酰基二硫缩烯酮，将其作为1，5-双亲电五碳合成子的[5+1]成环策略等。

Moreover, the polymeric arsine palladium(0) complex is an efficient catalyst for the carbonyl allylation of aldehydes and the coupling reaction of aryl halides with terminal alkynes or Grignard reagent.

该聚合物负载的胂钯(0)配合物还是醛的羰基烯丙基化及芳基卤化物与端炔、Grignard试剂的交叉偶联反应的有效催化剂。

These compounds include hydrocarbons, alcohols, ketons, aldehydes, esters and ringy compounds. The major volatile compounds are alcohols, aldehydes and ketons, respectively with the contents of

这些成分包括烃类、醇类、酮类、醛类、酯类和环状化合物，其中含量较高的是醇类、醛类、酮类，在腹部肉和背部肉中分别地占挥发性化合物总数的30.47%、38.47%、13.14%和27.87%、41.54%、14.43%。

Bis (P—bromobenzylamino) ethane and 1,2—bis (m—Iodobenzylamino) ethane may be prepared by condensation of the corresponding halo benzaldehyde with ethylenediamine and followed by catalytic hydrogenation of the Schiff's bases over Pto_2 in glacial acetic acid solutions: Both Ⅱa and Ⅱb may react in neutral mediam with aldehydes to form well—defined crystalline tetrahydro—imidazole, which may be served as derivatives of identification for aldehydes: Under the same condition, however,Ⅱb may ...

用1，2-二乙烷与二十余种醛类作用，得到有固定熔点的晶体衍生物，它们的熔点分布在85—210℃之间，产率为40—96％，这试剂与甲基酮类在相同条件下无反应，因此，它可作为鉴定醛类的专属试剂。 2。上述衍生物用稀盐酸在室溫处理，能发生水解，可以定量地收回原来的醛，因此这试剂又可作为分离醛类的试剂。 3。上述衍生物可以用非水滴定法半微量地测定其分子量可作为鉴定醛类的另一项参考数据。 4.1，2-二乙烷与醛类能生成晶体衍生物，但这试剂也与甲基酮在同样条件下发生反应，所以不适合作为鉴定醛类的专属试剂。

Aldol condensation of aldehydes with α-H in the base-catalyzed formation of carbon ions, and carbon ions as nucleophiles on aldehydes and ketones to increase the pro-nuclear ...

羟醛 缩合具有α-H的醛，在碱催化下生成碳负离子，然后碳负离子作为亲核试剂对醛酮进行亲核加。。。

Our group first reported a novel dialkylation reaction of alkyl zinc iodides with aromatic aldehydes and an olefination reaction of benzyl zinc bromides with aromatic aldehydes respectively.

我们实验室分别首次报道了在过渡金属络合物催化下带官能团有机卤化锌试剂与芳香醛的双烷化反应和烯基化反应。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。