Successive Michael reactions on chromone derivatives with dimethyl 1,3-acetonedicarboxylate: one-pot synthesis of functionalized benzophenones, benzo[c]chromones and hydroxybenzoylfuroates
作者:Michael A. Terzidis、Constantinos A. Tsoleridis、Julia Stephanidou-Stephanatou、Aristides Terzis、Catherine P. Raptopoulou、Vassilis Psycharis
DOI:10.1016/j.tet.2008.10.023
日期:2008.12
Chromones were reacted with dimethyl acetonedicarboxylate in the presence of DBU in THF at room temperature to furnish good yields of products, their structure depending on the substituent at 3-position. Unsubstituted chromones lead to methyl 7-hydroxy-6-oxo-6H-benzo[c]chromone-8-carboxylates 2, whereas by using 3-bromochromone, the methyl furoate 3c along with the unexpected furylcyclopropyl-chromene
在室温下,在DBU的存在下,于THF中使苯甲酮与丙酮二甲酸二甲酯反应,以提供良好的产物收率,其结构取决于3位的取代基。未取代的色酮导致7-羟基-6-氧代-6 H-苯并[ c ]色酮-8-羧酸甲酯2,而通过使用3-溴色酮,分离出糠酸甲酯3c以及意外的呋喃基环丙基-亚甲基羧酸酯4c。最后,从3-甲酰基-色酮中分离出官能化的二苯甲酮5,收率很高。提出了合理的机制。