查询词典 benzylic

Moreover,the selective oxidation of primary and secondary alcohols to corresponding carbonyl compounds with the multinuclear copper complexes Cul-Cu4 as catalysts have been conducted using TBHP and O_2/TEMPO,respectively.Among them,the copper complex Cu3 showed the best performance.On the performances of the two classes of oxidants,benzylic and heterocyclic alcohols could be effectively oxidized to carbonyl compounds.Specifically,the secondary alcohols could be effectively oxidized to ketones with excellent selectivity up to 100%in the presence of TBHP and the allylic alcohols could be effectively oxidized to aldehydes in the presence of O_2/TEMPO system.

实验结果还表明，在TBHP或O_2/TEMPO存在下，各配合物催化剂均能使各种取代芳香伯/仲醇以及杂环醇等以不同程度的转化率和选择性转化成相应的醛或酮，其中，配合物Cu3在O_2/TEMPO存在下可使苯甲醇和烯丙醇等以较高转化率和近100%的选择性转化成相应的醛，而对其它芳香醇和脂肪伯/仲醇等的催化性能则较差；在TBHP存在下，配合物Cu3则可使1-苯乙醇和其它仲醇以较高转化率和近100%的选择性转化为相应的酮，但对各类其它伯醇选择氧化的性能相对较差。

A polyurethane which is obtained from ingredients comprising a high-molecular polyol, an organic polyisocyanate, and a chain extender comprising a specific trifunctional isocyanurate compound having an aromatic hydroxyl group and/or a benzylic hydroxyl group, and which has a crosslinked structure due to the isocyanurate compound.

从包含高分子量多元醇、有机聚异氰酸酯和扩链剂的成分得到的聚氨酯，所述扩链剂包括含芳羟基和/或苄羟基的特定三官能团异氰脲酸酯化合物，并且其由于异氰脲酸酯化合物而具有交联结构。

Therelative rates of the Rh-mediated carbenoid insertion into the benzylic C - H bonds of aseries of para-substituted phenyl substrates: methyl 2-diazo-3-oxo-6-(4-substituted phenyl)-4-propylhexanoate 47a - g, have been measured by an indirect intramolecular competitionmethod under the condition in which the possible steric and conformational effects have beenminimized.

为了将立体因素和构象因素最大程度减小，以便较为准确地评价电子效应对该反应的影响，设计并合成了不同对位取代基的化合物4-丙基-6-(4-取代苯基)-2-重氮基-3-氧代己酸甲酯47a-g，并研究了它们在不同Rh催化剂作用下的分子内C-H插入反应。

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。