Abstract

A facile and efficient synthesis of novel seven-membered heterocyclic derivatives containing 3-aminoazepan-2-one backbone is described using 1,4-protected piperazine-2,5-diones and alkynes as starting materials. The reaction may undergo Michael­ addition, unusual nucleophilic attack to an amide group, and keto–enol tautomerization. The reaction showed different reactivity when using substrates with different protecting groups: it had higher efficiency when using either alkanoyl-protecting group with cesium carbonate as the base, or benzoyl-protecting group with triethylamine as the base, but no reaction when using benzyl or allyl protecting groups with a variety of bases (Et₃N, DBU, K₂CO₃, Cs₂CO₃, KHCO₃, CsHCO₃, and KOt-Bu).

A facile and efficient synthesis of novel seven-membered heterocyclic derivatives containing 3-aminoazepan-2-one backbone is described using 1,4-protected piperazine-2,5-diones and alkynes as starting materials. The reaction may undergo Michael­ addition, unusual nucleophilic attack to an amide group, and keto–enol tautomerization. The reaction showed different reactivity when using substrates with different protecting groups: it had higher efficiency when using either alkanoyl-protecting group with cesium carbonate as the base, or benzoyl-protecting group with triethylamine as the base, but no reaction when using benzyl or allyl protecting groups with a variety of bases (Et₃N, DBU, K₂CO₃, Cs₂CO₃, KHCO₃, CsHCO₃, and KOt-Bu).

中文翻译：

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一锅法合成多取代的3-氨基-2-氧代-2,7-二氢-1H-氮杂

摘要

描述了一种以1,4-保护的哌嗪-2,5-二酮和炔烃为起始原料轻松高效地合成含有3-氨基氮杂-2-酮主链的七元杂环衍生物的方法。该反应可能经历迈克尔加成反应，对酰胺基团的异常亲核攻击以及酮-烯醇互变异构。当使用具有不同保护基的底物时，反应显示出不同的反应性：使用以碳酸铯为碱的烷酰基保护基或以三乙胺为碱的苯甲酰基保护基时，反应具有更高的效率，但使用苄基或烯丙基时则无反应具有各种碱的保护基（Et ₃ N，DBU，K ₂ CO ₃，Cs ₂ CO ₃，KHCO₃，CsHCO ₃和KO t- Bu）。

描述了一种以1,4-保护的哌嗪-2,5-二酮和炔烃为起始原料轻松高效地合成含有3-氨基氮杂-2-酮主链的七元杂环衍生物的方法。该反应可能经历迈克尔加成反应，对酰胺基团的异常亲核攻击以及酮-烯醇互变异构。当使用具有不同保护基的底物时，反应显示出不同的反应性：使用以碳酸铯为碱的烷酰基保护基或以三乙胺为碱的苯甲酰基保护基时，反应具有更高的效率，但使用苄基或烯丙基时则无反应具有各种碱的保护基（Et ₃ N，DBU，K ₂ CO ₃，Cs ₂ CO ₃，KHCO₃，CsHCO ₃和KO t- Bu）。