有机膦酸钡负载的一类新型固体碱

首次用取代氨乙基膦酸H2O3PCH2CH2NR1R2(1a-f)与BaCl2反应合成了6种取代氨乙基膦酸钡BaO3PCH2CH2NR1R2载体(2a-f),载体经5%NaOH处理后制得固体碱(3a-f).固体碱用IR,TG,DTG,DSC,碱强度和水中游离碱量进行了表征,用指示剂法测得固体碱强度H-为9 3-15 0,用苯甲酸滴定法测定了载体和固体碱在水中的游离碱量.讨论了载体制备中,回流时间对载体和固体碱在水中的游离碱量的影响.固体碱用于催化Knoevenagel缩合反应,产率高,副反应少,可重复使用8次,且易于再生,是一种环境友好催化剂.

A New Type of Solid Base Supported on Barium Phosphonate

Barium substituted aminoethyl phosphonates BaO_3PCH_2CH_2NR~1R~2(2 a-f) as the supports were synthesized for the first time via reaction of barium chloride with substituted aminoethyl phosphonic acids H_2O_3PCH_2CH_2NR~1R~2(1 a-f). Solid bases(3 a-f) were prepared by treatment of the supports with 5% of sodium hydroxide solution, and characterized by IR, TG, DTG, DSC, basic strength and free base number in water. Basic strengths of the solid bases were about 9.3-15.0 by indicator method, the free base numbers of the supports or the solid bases in water were measured by using benzoic acid titration method, the effect of reflux time on the free base number of the supports or the solid base in water was discussed. Three types of Knoevenagel condensations catalyzed by the solid base were carried out in high yields, few side reactions and convenient workup. The solid base catalysts could be reused for 8 times and easy to be regenerated, it is a type of environmentlly friendly catalysts.