A continuous-flow synthesis of annulated and polysubstituted furans from the reaction of ketones and α-haloketones
作者:Mark York
DOI:10.1016/j.tetlet.2011.09.083
日期:2011.11
A synthesis of di-, tri- and tetra-substituted furans from reaction of the corresponding ketones and α-haloketones with LiHMDS is reported. Reaction under continuous-flow conditions gave increased yields and removed the need for external cooling when compared to the unoptimised batch conditions.
One-Pot Novel Regioselective Cycloisomerization Synthesis of 2-Substituted or 3-Substituted 4<i>H</i>-Furo[3,2-<i>c</i>]chromene through the Intermediate Cyclopropenes of 3-Diazochroman-4-one and Phenylacetylene
作者:Jin Gong、Zhensheng Zhao、Fuming Zhang、Songyun Wu、Guangqi Yan、Yingjie Quan、Baochun Ma
DOI:10.1021/ol502854y
日期:2014.11.7
A new class of cyclopropenes containing a chroman-4-one motif were synthesized using 3-diazochroman-4-one and phenylacetylene with rhodium(II) catalyst and followed by cycloisomerization to give 2-substituted or 3-substituted 4H-furo[3,2-c]chromene, respectively. Using BF3·Et2O as catalyst, 2-substituted 4H-furo[3,2-c]chromene was exclusively obtained in 70% yield. Using Cu(OTf)2 as catalyst, 3-substituted
使用3-重氮杂色-4-酮和苯乙炔与铑(II)催化剂合成了一类新的含色丁-4-酮基的环丙烯,然后进行环异构化,得到2-取代或3-取代的4 H-呋喃[3] ,2- c ]色烯。使用BF 3 ·Et 2 O作为催化剂,仅以70%的产率获得2-取代的4 H-呋喃[3,2- c ]亚甲基。使用Cu(OTf)2作为催化剂,进行3-取代的4 H-呋喃[3,2- c以95%的收率和98:2的区域选择性获得了] 1,1-二甲基苯。还开发了一种一锅级联加成-环异构化方法,无需分离苯并吡喃-4-one中间体的环丙烯。
Cu(<scp>ii</scp>)-catalyzed aerobic oxidative coupling of furans with indoles enables expeditious synthesis of indolyl–furans with blue fluorescence
processes, there has been a renewed focus on utilizing earth-abundant metal catalysts to expand the repertoire of organic reactions and processes. In this work, we have explored the atom-economic oxidative coupling between two important electron-rich heterocycles - indoles and furans - using commonly available, inexpensive metal catalyst CuCl2·2H2O (<0.25$ per g) to develop an expeditious synthesis