Sulfonation of 3-aroylthiophenes and furans with sulfuric acid in acetic anhydride regioselectively affords the corresponding 2,4-disubstituted heterocycle. Benzylamine derivatives of the parent sulfonamides are obtained either by Mannich reaction of aryl phenols, or via a sequence employing free radical bromination followed by selective ammonolysis. This methodology provides ready access to a wide
在
乙酸酐中区域选择性地用
硫酸磺化3-芳基
噻吩和
呋喃,得到相应的2,4-二取代的杂环。母体磺酰胺的
苄胺衍
生物可通过芳基
酚的曼尼希反应,或通过采用自由基
溴化后进行选择性
氨解的顺序获得。该方法学提供了对各种区域选择性取代的杂环的容易获得的途径。