Esterification of Phosphoric Acid with Equimolar Lauryl Alcohol Catalyzed by a Schiff Base Manganese Complex Anchored to a Keggin Heteropolyacid

Inorganic-organic hybrids were prepared by combining Schiff base complexes of manganese with silicotungstic acid (SiW). The composition and structure of the hybrid L1-Mn-SiW (L1: N,N′-disalicylidene-1,6-hexanediamine) were characterized by infrared spectroscopy and thermogravimetry. They were used as solid catalysts in the esterification of phosphoric acid with equimolar lauryl alcohol to monoalkyl phosphate ester (MAP). Over the L1-Mn-SiW catalyst, the yield and selectivity for MAP were 93% and > 98%, respectively, at the optimal reaction conditions. The catalyst exhibited excellent recoverability during a six-cycle test without any observable change of the catalyst structure. A base-catalyzed reaction route was proposed.

摘要将席夫碱锰配合物与硅钨酸结合制备出一种新颖的无机-有机杂化固体催化剂,通过红外光谱和热重表征数据推测出这种催化剂的组成和结构,并将其用于磷酸与等摩尔月桂醇酯化制备长链单烷基磷酸酯(MAP).结果表明,采用L1-Mn-SiW(L1:双水杨醛缩-1,6-己二胺)催化剂,在优化的反应条件下,酯化反应可获得93%的MAP收率和高达98%的MAP选择性.催化剂的重复使用测试表明,液-固多相酯化体系中该固体催化剂可方便地回收,且具有优异的稳定性,重复使用6次后催化剂活性未见下降,结构没有变化,是高效绿色催化剂.该催化剂作用下的磷酸酯化是固体碱催化过程.

In the esterification of phosphoric acid with equimolar lauryl alcohol, the new solid catalyst prepared by anchoring a Schiff base manganese complex to silicotungstic acid exhibits a very high yield and selectivity for phosphoric acid monoester with excellent reusability.Figure optionsDownload as PowerPoint slide