Reactions of cyclic β-alkoxyvinyl α-keto esters with heteroaromatic NCC-binucleophiles
作者:Oleksandr O. Stepaniuk、Bohdan V. Vashchenko、Vitalii O. Matvienko、Ivan S. Kondratov、Andrey A. Tolmachev、Oleksandr O. Grygorenko
DOI:10.1007/s10593-020-02670-z
日期:2020.3
Reactions of five- and six-membered cyclic β-alkoxyvinyl α-keto esters and NCC-binucleophiles are described. The following binucleophiles were studied: heteroaromatic amines (pyrazoles, isoxazole, uracils, and isoquinolinone) and 2-(benzimidazolyl)acetonitrile. It was found that condensation proceeded regioselectively in the case of five-membered cyclic enone. Fused α-pyridine carboxylates, likely
描述了五元和六元环状β-烷氧基乙烯基α-酮酯与NCC-双亲核试剂的反应。研究了以下双亲核试剂:杂芳族胺(吡唑,异恶唑,尿嘧啶和异喹啉酮)和2-(苯并咪唑基)乙腈。发现在五元环状烯酮的情况下,缩合选择性地进行。熔融的α-吡啶羧酸盐,可能原位形成,进行内酯化,产生六元内酯,产率中等至优异(53-91%)。仅在3-未取代的5-氨基吡唑的情况下,观察到形成γ-吡啶羧酸酯,然后环化成异构内酯。相反,在优化条件下,六元环烯酮仅对杂环胺具有反应性,并以40-80%的产率提供开链α-吡啶羧酸酯。