硼酸和γ-氧化铝作为Lewis酸性固体模型物的热化学研究  

A THERMOCHEMICAL STUDY ON THE ESTABLISHMENT OF SOLID MODEL OF LEWIS ACIDITY

作　　者：刘祁涛[1] 张向东[1] 蒋湘顺[1] 薛邦明 姜卉[1] 

机构地区：[1]辽宁大学化学系,沈阳110036

出　　处：《应用化学》1993年第2期78-80,共3页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金

摘　　要：本文用热化学方法研究某些ⅢA族元素的含氧化合物与多种有机碱类的相互作用,试建立Lewis酸性的固体模型,探讨复相酸碱反应的机理。硼酸在室温是一种稳定的固体酸,在水溶液中的酸性来源于水中OH^-离子在中心硼原子上的配位,而不是硼酸分子自身解离给出质子。这显示了典型的Lewis酸性。固体硼酸也可能成为一个Lewis酸的固体模型。The heats of immersion of orthoboric acid in twelve organic bases and the adsorption heats of nine organic bases on γ-alumina were determined. The heat values were correlated with the corresponding enthalpies of boron trifluoride and antimony penta chloride, the well-known homogeneous prototype of Lewis acid. The results show that the heats of immersion of H_3BO_3 appear to be well correlated with the thermochemical measurements of BF_3 and SbCl_5 (correlation coefficient are 0. 98 and 0.97 respectively), but the correlation coefficient for the adsorption heats of γ-Al_2O_3 and the two homogeneous prototype of Lewis acid are only 0.95 and 0. 92 respectively. It is concluded that the reaction of orthoboric acid with the organic bases is an essential Lewis acid-base interaction and the orthoboric acid could be used as a solid prototype of Lewis acid.

关 键 词：电子接受体 硼酸 氧化铝 固体 

分 类 号：O614.31[理学—无机化学]