Regioselective combination of 1,3-dinucleophiles such as 2-mercaptobenzimidazole, 5-mercapto-3-phenyltriazole and potassium thiocyanate with 2,2-dicyanooxiranes
作者:Mohammad Seifi、Hassan Sheibani
DOI:10.3998/ark.5550190.p008.002
日期:——
3]thiazole with benzimidazole or triazole derivatives were obtained by the regioselective reactions of the 2,2-dicyanooxiranes with 1H1,3-benzimidazol-2-thiol or 5-phenyl-4H-1,2,4-triazol-3-thiol respectively in good to excellent yields. Also, we performed a reaction between 2,2-oxiranedicarbonitrile reagents and potassiumthiocyanate in acetic anhydride at room temperature and isolated 2-acetylimino-1,3-oxathiole
Regioselective ring opening of 2,2-dicyanooxiranes by 1,3-dinucleophiles in the presence of Lewis acids such as bismuth(III) nitrate pentahydrate [Bi(NO3)3·5H2O] and zirconium(IV) chloride (ZrCl4)
or zirconium(IV) chloride (ZrCl4) has been shown to catalyze nucleophilic ring opening of 2,2-dicyanooxiranes along with ringclosure by 1,3-dinucleophiles such as 1 H -1,3-benzimidazole-2-thiol, 5-phenyl-4 H -1,2,4-triazole-3-thiol, and thioureas. These reactions led to efficient synthesis of heterocyclic compounds condensed with benzimidazole or triazole derivatives. The used catalysts are inexpensive
硝酸铋(III)五水合物[Bi(NO 3)3 ·5H 2 O]或氯化锆(IV)(ZrCl 4)已显示出可以催化1,2-二氰基氧杂环戊烷的亲核开环以及1,3的闭环-二亲核试剂,例如1 H -1,3-苯并咪唑-2-硫醇,5-苯基-4 H -1,2,4-三唑-3-硫醇和硫脲。这些反应导致与苯并咪唑或三唑衍生物缩合的杂环化合物的有效合成。所用的催化剂便宜,高效且可在环境温度下用于以1,3-二亲核试剂打开环氧化物,具有出色的区域选择性。