一种简单高效的区域选择性合成异恶唑基-1,4-二取代-1,2,3-三唑6a,6b,6c,6d,6e,6f,6g,6h,6i,6j,6k,6l的方法描述了具有异恶唑骨架4a,4b,4c和各种叠氮化物的末端炔烃通过Cu(I)催化的1,3-偶极环加成反应的良好至优异的收率。反应在t的1:1混合物中平稳进行-室温下加BuOH和水。根据光谱数据ir,1 H nmr,质量和元素分析,确定所有新合成的杂合杂环的结构。
Zn(OTf)<sub>2</sub>-Catalyzed Formal [3 + 3] Cascade Annulation of Propargylic Alcohols with 2-Aminochromones: Accessing the Chromeno[2,3-<i>b</i>]pyridines
作者:Pei Tong、Zhou Sun、Shutao Wang、Yuan Zhang、Ying Li
DOI:10.1021/acs.joc.9b02120
日期:2019.11.1
A Zn(OTf)2-catalyzed formal [3 + 3] cascade annulation strategy for the synthesis of functionalized chromeno[2,3-b]pyridines has been developed using propargylicalcohols and 2-aminochromones as the substrates. The protocol provides a convenient and atom-economical method of accessing a broad range of chromeno[2,3-b]pyridine derivatives in excellent yields with good functional-group tolerance. The
Reaction of chromones with hydroxylamine in anhydrous methanol
作者:Vince Szabó、János Borbély、Edit Theisz、Sándor Nagy
DOI:10.1016/s0040-4020(01)87646-8
日期:1986.1
The reaction of 4H-1-benzopyran-4-one (chromone, ,) and its substituted derivatives with hydroxylamine in aqueous alcohols gives isoxazoles and , as the major products, whereas is transformed mainly into with hydroxylamine hydrochloride in anhydrous methanol, compounds , and can be also isolated, and the formation of and has been detected, as well. Depending on the character of the substituent, substituted