以自制的正构长链烷基酚为原料与多聚甲醛在碱性催化剂下进行羟甲基化反应,生成2,6-二羟甲基-4-烷基苯酚,再与另两分子烷基酚在固体超强酸催化下进行缩合反应生成2,6-二(5-烷基水杨基)-4-烷基苯酚,用核磁共振氢谱和碳谱、红外光谱和元素分析对产物进行了结构鉴定,探讨了催化剂、反应物料配比、反应时间等条件对产物产率的影响.另外根据上述反应路线,以工业品壬基酚和多聚甲醛为原料,经羟甲基化反应、缩合反应合成了2,6-二(5-壬基水杨基)-4-壬基苯酚.上述两种结果表明,选用SO24-/SnO2固体超强酸作催化剂,2,6-二羟甲基-4-烷基苯酚和烷基酚的配比为1:2,140℃反应2h,产率达到95%.
Five intermediates for preparing long chain n-alkylphenol trimeric surfactants, 2,6-bis(5-alkyl-salicyl)-4-alkylphenol, were synthesized from fatty acid, phenol, and paraformaldehyde through Friedel-Crafts acylation, estedfication, Fries rearrangement, Huang Minion reduction, alkaline catalytic re-action, and condensation reaction by virtue of solid superacid, and their molecular structures were confirmed by NMR, IR techniques and elemental analysis. According to this synthetic route of 2,6-bis(5-alkyl-salicyl)-4-alkylphenol, 2,6-bis(5-nonylsalicyl)-4-nonylphenol has also been synthesized by using isononyl-phenol (industrial product) and paraformaldehyde successfully. It was showed that when 2,6-bis-(hydroxymethyl)-4-alkylphenol and alkylphenol were reacted at a molar ratio of 1 : 2 at 140 ℃ for 2 h, the product yield could reach 95%.