Expeditious synthesis of pyrano[2,3,4-de]quinolines via Rh(<scp>iii</scp>)-catalyzed cascade C–H activation/annulation/lactonization of quinolin-4-ol with alkynes
作者:Gang Liao、Hong Song、Xue-Song Yin、Bing-Feng Shi
DOI:10.1039/c7cc04113f
日期:——
One-step synthesis of tetracyclic pyrano[2,3,4-de]quinolones via Rh(iii)-catalyzed cascade C–H activation/annulation/lactonization is described.
Herein, an efficient and regioselective Rh(III)‐catalyzed [4+2] annulation/lactonization cascade of indoles with 4‐hydroxy‐2‐alkynoates at room temperature to access the furo[3′,4′:4,5]pyrimido[1,6‐a ]indole‐1,5(3H ,4H )‐diones is described. This method features mild reaction conditions, operational simplicity, excellent regioselectivity, broad substrate scope with good functional group tolerance,
本文中,在室温下高效和区域选择性的Rh(III)催化吲哚的[4 + 2]环化/内酯化级联反应,其具有4-羟基-2-链烷酸酯,可进入呋喃[3',4':4,5]嘧啶描述了[ 1,6 - a ]吲哚-1,5 (3 H,4 H)-二酮。该方法的特点是反应条件温和,操作简便,区域选择性出色,底物范围广,具有良好的官能团耐受性以及良好的产率。
One‐Pot Synthesis of Fused
<i>N,O</i>
‐Heterocycles through Rh(III)‐Catalyzed Cascade Reactions of Aromatic/Vinylic
<i>N</i>
‐Alkoxy‐ Amides with 4‐Hydroxy‐2‐Alkynoates
作者:Yuanshuang Xu、Bin Li、Xinying Zhang、Xuesen Fan
DOI:10.1002/adsc.201800190
日期:2018.7.16
group. To the best of our knowledge, this is the first example in which both the furan‐2(5H)‐one and the pyridin‐2(1H)‐one scaffolds are constructed in onepot under one set of reaction conditions. Compared with literature methods, notable features of this new protocol include facile formation of bis‐heterocyclic scaffolds from readily available acyclic substrates, broad substrate scope with good tolerance
呋喃并[3,4- c ]异喹啉-1,5 (3 H,4 H)-二酮和呋喃并[3,4- b ]吡啶-2,5(1 H,7 H)的高效区域选择性合成介绍了通过Rh(III)催化的芳族/乙烯基N-烷氧基酰胺与4-羟基-2-炔基酯的一锅级联反应的二酮。从机理上讲,Rh(III)催化的惰性C(sp 2)-H键活化酰胺底物,然后使其[4 + 2]环化并用具有氧化和部分无痕导向基团的4-羟基-2-炔基内酯进行内酯化。就我们所知,这是第一个实例,其中在一组反应条件下,在一个锅中构建了呋喃2(5 H)-1和吡啶2(1 H)-1支架。与文献方法相比,该新方案的显着特征包括从易于获得的无环底物轻松形成双杂环支架,宽广的底物范围和对各种官能团的良好耐受性,极佳的区域选择性和高效率。