Synthesis of 2-Amino-1,3-benzoselenazole via Metal-Free Cyclization from Isothiocyanate and Bis(o-aminophenyl)diselenide
作者:Hayato Ichikawa、Naoka Miyashi、Yui Ishigaki、Minako Mitsuhashi
DOI:10.3987/com-19-s(f)46
日期:——
Amino-1,3-benzoselenazoles were generated from the reactions of bis(o-aminophenyl)diselenide and various isothiocyanates under metal-free cyclization conditions. The cyclization of isothiocyanate bearing bulky substituents proceeded in excellent yields because the amounts of byproducts generated were reduced. Acid hydrolysis of acetamide produced 2-amino-1,3-benzoselenazole (4). Benzothiazole, a bioisostere
氨基-1,3-苯并硒唑是由双(邻氨基苯基)二硒化物和各种异硫氰酸酯在无金属环化条件下反应生成的。带有大取代基的异硫氰酸酯的环化以优异的收率进行,因为产生的副产物的量减少了。乙酰胺的酸水解产生 2-氨基-1,3-苯并硒唑 (4)。苯并噻唑是苯并恶唑的生物等排体,是在药物、农药、天然产物和材料化学中发现的最具吸引力的杂环化合物之一。特别是,2-氨基-1,3-苯并噻唑具有多种生物学和药理学特性。例子包括利鲁唑,对双子叶和单子叶杂草的除草活性,以及单偶氮分散染料,和衍生化为这些化合物作为有机合成中间体的广泛使用铺平了道路(图 1)。图 1. 苯并噻唑 NS NH2 F3CO NS NH