可膨胀石墨催化合成3,3,6,6-四甲基-9-芳基-1,2,3,4,5,6,7,8-八氢化氧杂蒽-1,8-二酮

Synthesis of 3,3,6,6-Tetramethyl-9-aryl-1,2,3,4,5,6,7,8-octahydro-xanthene-1,8-dione Catalyzed by Expansible Graphite

在可膨胀石墨催化下,由芳香醛和5,5-二甲基-1,3-环己二酮缩合制备了3,3,6,6-四甲基-9-芳基-1,2,3,4,5,6,7,8-八氢化氧杂蒽-1,8-二酮.在乙醇-水介质中回流反应2.5h,反应产率可达87%～93%.该方法不仅反应时间短,产率高,而且催化剂价廉易得、对环境友好,催化剂经简单过滤后可重复使用.

A novel synthesis of 3,3,6,6-tetramethyl-9-aryl-1,2,3,4,5,6,7,8-octahydroxanthene-1,8-dione via condensation of aromatic aldehydes with 5,5-dimethyl-1,3-cyclohexanedione using expansible graphite as catalyst was described. The reaction time was 2.5 h, and the yield ranged from 87% to 93%. The catalyst was inexpensive and environmental friendly, and could be recovered by filtration.