Synthesis,characterization of amine-bridged bis (phenolate) yttrium alkyl complex and its catalytic behavior for the Tishchenko reaction

Reaction of homoleptic yttrium tris-alkyl complex YR3 (R=CH2C6H4NMe2-o) with 1 equivalent of amine bis(phenol)s LH2 (L=Me2NCH2CH2N(CH2-(2-O-C6H2-But2-3,5))2) afforded the solvent-free yttrium alkyl complex LYR (1),which has been characterized with elemental analysis,1H NMR and IR spectra,and structural determination. The coordination geometry around the center metal atom can be best de-scribed as a distorted octahedron. It was found that complex 1 can be used as an efficient catalyst for the Tishchenko reaction.

三烷基钇配合物合成及在催化Tishchenko反应中的应用

烷基稀土金属配合物由于其较高的催化活性,近年逐渐成为人们的硏究热点。而正由于其不稳定,易发生配体再分配或β-H消除等反应.若要使其穏定,则需采取其他措施。在无水无氧的条件下,利用2-(二甲胺基)苄基锂盐LiR(R=CH2C6H4-NMe2-o)与三氯化钇反应制得相应的三烷基钇配合物YR3。配合物YR3能够有效地催化Tishchenko反应,反应条件温和,产率中等。

丙醇铝催化丙醛一步合成丙酸丙酯

用丙醇和铝粉直接合成了丙醇铝,确定了合成丙醇铝的工艺条件为:2％AlCl_3,0.1％碘,n(铝):n(丙醇)=1:6,反应温度90℃。在该工艺条件下,反应仅需50 min,丙醇铝收率可达 98％。以合成出的丙醇铝为催化剂,无水氯化锌为助催化剂,用丙醛一步合成了丙酸丙酯,收率可达92％,选择性可达93％。

Kinetic Study of the Aldol Condensation of Isobutyraldehyde Catalyzed by Sodium Hydroxide

The initial step of works on the designing of a mathematical model of a commercial process to manufacture a mixture of butyric acid hydroxyesters, for use in ecological solvent compositions for the paint and varnish industry, is presented in the paper. The works referred to in this paper relate the mathematical model of the condensation reactor. A unit process kinetic model was designed based on an analysis of the general differential form of the equation of the reactor mass balance and an analysis of the mechanism of the Tishchenko aldol condensation reaction, as used in the synthesis of butyric acid hydroxyesters, confirmed by the results of GC/MS analysis. The forms of the kinetic equations obtained were verified experimentally by determining the values of the respective reaction rate constants.

醇钠催化苯甲醛合成苯甲酸苄酯——介绍一个探索性有机化学实验

本实验以大学生创新实验为背景,以培养学生创新能力为目的,结合有机化学实验的特点,设计了苯甲酸苄酯的合成路线。以苯甲醛为原料、苯甲醇钠为催化剂,经Tishchenko反应合成目标产物。其最佳合成条件为:苯甲醛与醇钠物质的量比为33:1,反应温度介于50-60°C,反应时间为1 h。产率69%,产品纯度99%以上。实验结果表明,此工艺流程符合有机化学实验的要求。