Acceptorless dehydrogenative condensation: synthesis of indoles and quinolines from diols and anilines
作者:Delia Bellezza、Ramón J. Zaragozá、M. José Aurell、Rafael Ballesteros、Rafael Ballesteros-Garrido
DOI:10.1039/d0ob01964j
日期:——
The use of diols and anilines as reagents for the preparation of indoles represents a challenge in organic synthesis. By means of acceptorless dehydrogenative condensation, heterocycles, such as indoles, can be obtained. Herein we present an experimental and theoretical study for this purpose employing heterogeneous catalysts Pt/Al2O3 and ZnO in combination with an acid catalyst (p-TSA) and NMP as
使用二醇和苯胺作为制备吲哚的试剂代表了有机合成中的挑战。通过无受体的脱氢缩合,可以获得诸如吲哚的杂环。本文中,我们针对此目的进行了实验和理论研究,将多相催化剂Pt / Al 2 O 3和ZnO与酸催化剂(p-TSA)和NMP作为溶剂。在我们优化的条件下,二醇过量已减少至2当量。这代表了重大进步,并允许使用其他二醇。已使用2,3-丁二醇或1,2-环己二醇,得到2,3-二甲基吲哚和四氢咔唑。另外,已将1,3-丙二醇用于制备喹啉或天然和合成的聚甲基吡啶。