无溶剂超声辐射下琥珀酸二酰亚胺磺酸铈催化合成5-[(3-吲哚基)-甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物

Solvent-Free Synthesis of 5-[(Indol-3-yl)-methyl]-2,2-dimethyl-1,3-dioxane-4,6-dione Derivatives under Ultrasonic Irradiation with Succinimide-N-sulfonic Acid Cerium as Catalyst

在琥珀酸二酰亚胺磺酸铈催化下,吲哚、醛和2,2-二甲基-1,3-二噁烷-4,6-二酮在无溶剂条件下超声辐射合成了10种5-[(3-吲哚基)-甲基]-2,2-二甲基-1,3-二噁烷-4,6-二酮衍生物.当催化剂的用量为3%(摩尔分数)时,30℃反应30~60 min,收率为68.9%~96.7%.此外,还探讨了琥珀酸二酰亚胺磺酸铈的催化机理.该方法具有条件温和,反应时间短且收率高的优点.催化剂邻琥珀酸二酰亚胺磺酸铈对环境友好且可循环利用.

Ten kinds of 5-[(indol-3-yl)-methyl]-2,2-dimethyl-1,3-dioxane-4,6-dione derivatives were synthesized by the three component condensation reaction of indole with aldehydes and 2,2-dimethyl-1,3-dioxane-4,6-dione using succinim-ide-N-sulfonic acid cerium as catalyst under solvent-free and ultrasonic irradiation. The results indicated that the yields ranged from 68.9% to 96.7%, when using 3%(molar fraction) succinimide-N-sulfonic acid cerium and reacting at 30 ℃ for 30 to 60 min. Furthermore, a proposed reaction mechanism for the reaction catalyzed by succinimide-N-sulfonic acid cerium was speculated. The main advantages of the present procedure were milder conditions, shorter reaction time and higher yields. Further study showed that succinimide-N-sulfonic acid cerium was environmentally friendly and reused for six times without any noticeable decrease in the catalytic activity.