三苯甲基

A new way of synthesis 2-methoxy-4'-trifluoromethyl acetophenone by the method of crossed ester condensation was investigated in the overall yield of higher than 85%.

本文提出了一种新的方法——交叉酯缩合法合成2-甲氧基-4'-三氟甲基苯乙酮。

The method for synthesizing 2- benzofuran derivatives has easily available raw material, simple process, easy realization and high yield.

合成2位三氟甲基取代的苯并呋喃衍生物的方法，原料容易得到，合成工艺简单，易行，产率较高。

Synthesis of trifluoromethylbenzene by fluorination of trichloromethylbenzene with hydrogen fluoride was investigated.

三氟甲基苯是一种重要的有机化工中间体，广泛应用于医药农药染料等领域。

Triphenyl phosphite provided prominent stabilization only when used in combination with other stabilizers. Good results have been obtained for both polyether-urethane and nitrate esters when using 2,6-di-t-butyl-4-methyl-phenol as stabilizer.

亚磷酸三苯酯单独使用时效果较差，但与其它种类的稳定剂混合使用能得到较好的效果。2，6-二叔丁基-4-甲基酚对硝酸酯和聚氨酯粘结剂均具有良好的稳定作用。

In pH 5.3-6.8 Britton-Robinson buffer medium, Cefotaxime sodium can react with HgCl2 to form 1:1 anionic chelate, which can further react with basic triphenylmethane dye such as crystal violet, methyl violet, ethyl violet, brilliant green, iodine green, methyl green and malachite green to form ternary ion-association complexes. As a result, the resonance Rayleigh scattering spectrum was enhanced greatly.

在pH为5.3~6.8的Britton-Robinson缓冲溶液中，头孢噻肟钠与HgCl2形成摩尔比为1：1的螯合阴离子，它能进一步与结晶紫、甲基紫、乙基紫、亮绿、碘绿、甲基绿和孔雀石绿等碱性三苯甲烷类染料反应形成三元离子缔合物，导致共振瑞利散射的显著增强。

Arsonium ylide ; crystal structure ; dimethyl 2-benzoymethylene-3-triphenylarsylene-succinate

胂叶立德；晶体结构； 2-苯甲酰亚甲基-3-三苯胂叉琥珀酸二甲酯

Its derivatives such as trifluoromethyl benzotriazole are widely used in biochemistry, medicine, pesticides and other areas.

其衍生物如三氟甲基苯并三氮唑等在生物化学、医药、农药等领域得到了广泛的应用。

The main products are: phosphorous trichloride 300,000 tons / year, phosphorus oxychloride 100,000 tons / year, phosphorus pentachloride 50,000 tons / year, 10,000 tons trichloroisocyanuric parathion / year chloromethyl ether 5000 tons / year, triethyl phosphite 10,000 tons / year, triphenyl phosphite 5000 tons / year, three phosphoric acid ethyl butoxy 2000 tons / year.

主要产品有：三氯化磷30万吨/年、三氯氧磷10万吨/年、五氯化磷5万吨/年、三氯硫磷1万吨/年、氯甲基甲醚5000吨/年、磷酸三乙酯10000吨/年、磷酸三苯酯5000吨/年、磷酸三丁氧基乙酯2000吨/年。

The first and second generation of dendritic polyesters have been prepared by divergent synthetic ways using trimethylopropame as core and o-phthalic anhydride, glycidol as branched units.

以三羟甲基丙烷为核，邻苯二甲酸酐，环氧丙醇为支化结构单元，合成了第一及第二代树枝状聚酯。

The Mannich-type addition of O , O'-dialky phosphite to 2-fluorobenzaldehyde and 4-trifluoro- methylaniline was carried out in one pot by means of adopting three kinds of green synthetic methods, microwave irradiation, ionic liquid and free solvent-catalyst condition. According to the results, the synthetic method was optimized without catalyst and solvent at 100 ℃ and 15 min, and it was economic, convenient, high yields, timesaving and environment friendly.

采用微波辐射﹑离子液体和无溶剂无催化剂三种绿色合成方法，分别进行了以亚磷酸酯、邻氟苯甲醛和对三氟甲基苯胺为原料的类Mannich一锅法合成反应研究，经合成筛选，优选出控制反应温度100 ℃、无溶剂和无催化剂加热反应15 min的合成方法，实验结果表明该方法经济、简便、产率高、反应时间短及对环境友好。

Now, however, all children continue in "comprehensive" schools, and the eleven-plus determines which courses of study the child will follow.

然而现在，所有的孩子都要在综合学校继续学习，所以这次考试只是决定他们将要学习哪些课程。

Cultivatable land , and led to a general recognition that development must not be carried at the cost of agriculture .

城区的迅速扩大在很多情况下侵占了宝贵的可耕地，使人们普遍认识到发展不能以牺牲农业为代价。