of surface area and Lewis acid sites was observed with increase of Al content. The catalysts have been applied as heterogeneous catalysts to synthesize pyrido[1,2-a]pyrimidines under mild reaction conditions. A variety of biologically active pyrido[1,2-a]pyrimidines were obtained in best yields ever (above 90%) by using a simple, eco-friendly and efficient protocol catalyzed by AlxH3−xPW12O40 catalysts
采用简单的离子交换法制备了具有Keggin结构的铝交换
钨磷酸盐(Al x H 3− x PW 12 O 40)。通过各种技术,如元素分析,XRD,FTIR,UV-vis,N 2-物理吸附,NH 3 -
TPD和FTIR-
吡啶吸附,对制备的杂多酸盐进行了表征。所有制备的催化剂都具有布朗斯台德和
路易斯酸位点,但是随着铝含量的增加,表面积和
路易斯酸位点增加。该催化剂已被用作非均相催化剂,以在温和的反应条件下合成
吡啶并[1,2- a ]
嘧啶。多种具有
生物活性的
吡啶基[1,2-通过使用由Al x H 3− x PW 12 O 40催化剂催化的简单,环保和高效的方法,可以以最高的收率(90%以上)获得a ]
嘧啶。Al 3 PW 12 O 40催化剂显示出最高的活性,这是由于通过Al 3+离子完全交换H +离子将更多的
路易斯酸位引入母体H 3 PW 12 O 40。