ABSTRACT 3-Prop-2′-ynyloxybenzothiapyran-4-one derivatives (3a–d) were prepared from 3-hydroxy benzothiapyran-4-one (1) and prop-2-ynylic halides (2) in 70–90% yield. The ethers (3a–d) were then heated in refluxing chlorobenzene to give furo[3,2-b]benzothiapyran-9-one derivatives (4a–d) in 87–95% yields. 2-Chloro-2-methylbut-3-yne (2e) on reaction with 3-hydroxybenzothiapyran-4-one (1a) directly afforded
摘要 3-Prop-2'-ynyloxybenzothiapyran-4-one 衍
生物 (3a-d) 是由 3-羟基 benzothiapyran-4-one (1) 和 prop-2-ynylic halides (2) 以 70-90% 的产率制备的。然后将醚 (3a-d) 在回流的
氯苯中加热,以 87-95% 的产率得到
呋喃 [3,2-b] benzothiapyran-9-one 衍
生物 (4a-d)。2-Chloro-2-methylbut-3-yne (2e) 与 3-hydroxybenzothiapyran-4-one (1a) 反应直接得到 2-isopropyl furo[3,2-b]benzothiapyran-9-one (4e) 在 70 % 屈服。