Benzopyrans. Part 30. Synthesis of substituted xanthones from 3-acyl-2-methyl-1-benzopyran-4-ones
作者:Chandra Kanta Ghosh、Sirin Sahana、Amarendra Patra
DOI:10.1016/s0040-4020(01)89924-5
日期:1993.5
The xanthone 8 results from the base catalysed self-condensation of the chromone 1. The chromone 2 gives the xanthones 9 and 11 with sodium and DMF-POCl3 respectively, phenol 14 with NaOMe, and the pyran 22 with 2-thiomethylchromone 6. The enamine 16 on Vilsmeier-Haak reaction affords the chloroxanthone 12. The pyran 15, isolated as a byproduct from the reaction of ω-acetyl-2-hydroxyacetophenone with
an吨酮8是由色酮1的碱催化的自缩合产生的。色酮2分别为氧杂蒽9和11加上钠和DMF-POCl 3,苯酚14含有NaOMe,而吡喃22含有2-硫代甲基色酮6。Vilsmeier-Haak反应中的烯胺16提供了氯吨蒽酮12。从ω-乙酰基-2-羟基苯乙酮与HC(OEt)3 -Ac 2 O的反应中分离出的副产物吡喃15提供了x吨酮13 通过与NaOMe在MeOH中的回流进行回流。