作者:Yonghong Liu、Shengrong Liao、Chun Qin、Peifen Yao、Jinsheng Li、Xuefeng Zhou、Junfeng Wang、Zhishu Huang
DOI:10.1055/s-0033-1340473
日期:——
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).