查询词典 bromination

One synthetic strategy started fromγ-butyrolactone 38, from which a cyclohexadiene intermediate 30 was prepared in an overall yield of 44% in a 7-step procedure after y-butyrolactone underwent a-bromination, dehydrobromination, Diels-Alder reaction, aminolysis, benzylation, bromination and dehydrobromination, with the key step being the Diels-Alder reaction under harsh condition.

其中一个路线从γ-丁内酯38开始，连续经过α-溴化、脱溴化氢、Diels-Alder反应、胺解、苄基化、溴化和脱溴化氢共7步反应，制备了一个环己二烯衍生物30，总产率44％，关键步骤是高温高压下Diels-Alder反应。

Then 2′bromo-2-dimethylamino-1,1′-binaphthyl was obtained via diazotization,bromination and methylation in 49.7% yield.

首先，它是在有机化学和无机化学的相互渗透中发展起来的，此外，它还和一些相关学科具有密切联系。

In cases of doubt the changes following hydrogenation, bromination or other chemical attack upon the double bond can be studied.

在有疑问时可以研究双键的氢化，溴化或其他化学反应所引起的变化。

Determination of Pentosan Content in Bamboo by Bromination Method;2. The wheat straw contains abundant cellulose and pentosan .

麦草含大量的纤维素和聚戊糖，其中的纤维素在纤维素酶的作用下分解生成葡萄糖和纤维二糖。

A series of 5-bromopyrimidinyl-containing new sulfonylureas have been synthesized through bromination of 2-amino-4-methyl pyrimidine, followed by further modification and then coupled with sulfonyl isocyanate.

通过2-氨基-4-甲基嘧啶溴代反应以及进一步的衍生、磺酰基异氰酸酯的胺解，合成了一系列含有5-溴嘧啶基的新磺酰脲。

Master the Keto-Enol tautomerism; reactions of enols:α-H substitution reactions;α-halogenation of aldehydes and ketones;α-bromination of carboxylic acids; acidity ofα-H atoms: enolate ion formation; reactivity of enolate ions; alkylation of enolate ions; mechanism of carbonyl condensation reactions;condensations of aldehydes and ketones: the Aldol reaction; dehydration of Aldol products; the Claisen condensation reaction; the Michael addition.

熟练掌握酮式－烯醇式互变异构；烯醇的反应：α-H的活性；醛酮的α卤代反应；羧酸的α-溴代反应；α-H的酸性：烯醇负离子的形成；烯醇负离子的反应；烯醇负离子的烃基化；羰基化合物的缩合反应机理；醛酮的缩合反应－Aldol缩合；Aldol缩合产物的脱水反应； Cleisen 酯缩合反应；麦克尔加成反应。

Vanillin 58 was used as starting material, which underwent methylation, bromination, acetalization, lithiation followed by nucleophlic addition to aldehyde, Diels-Alder reaction, selective reduction and lactonization to produce diphyllin in an overall yield of 38%(7 steps).

这个方法从香兰素58开始，经过甲基化、溴化、成乙二醇缩醛反应、锂化而后对醛亲核加成、Diels-Alder反应、选择性还原反应和内酯化反应共7步，最后得到diphyllin，总产率38％。

Bromination occur s selectively on the PMS methyl group, providing a reactive benzylic bromine functionality which is the key to Exxpro specialty elastomers′ vulcanization and modification versatility.

溴化反应选择性地发生在PMS的甲基基团上，提供活性苄基溴官能团，这也是Exxpro特种弹性体硫化和各种改性的关键。

Bromination occurs selectively on the PMS methyl group, providing a reactive benzylic bromine functionality which is the key to Exxpro specialty elastomers′ vulcanization and modification versatility.

溴化反应选择性地发生在PMS的甲基基团上，提供活性苄基溴官能团，这也是Exxpro特种弹性体硫化和各种改性的关键。

The effects of different ratio of reacting material, concentration and temperature were studied in the bromination reactions.

研究了溴化反应中反应物物质的量比、反应物浓度、温度付溴代反应的影响。

I was just taking her hand, to help her out of a car, and I knew it.

我只是握着她的手，扶她下车，但我知道这一切。

China and South Korea have excoriated Japan over its approval of new school books which they say whitewash the atrocities committed during Japanese occupation, and anti-Japanese protests have been held in Chinese cities. The lingering bitterness over Japan's past imperialism still threatens to mar relations between the big East Asian powers

中国和韩国强烈谴责日本通过新的中学历史教科书，他们认为这一教科书掩盖了日本在其占领期间所犯下的残酷暴行，反日抗议活动在中国数座城市发生，历史上日本帝国主义制造的痛楚无法被忘却，这有可能破坏东亚强国间的关系。