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。
Tetrahydrocarbazoles by mechanochemical Fischer indolisation
作者:Yichen Qiu、Kararaina Te Puni、Clotilde C. Duplan、Ashley C. Lindsay、Jonathan Sperry
DOI:10.1016/j.tetlet.2021.153068
日期:2021.5
The Fischer indolisation (FI) typically proceeds in the presence of a Brønsted or Lewis acid in an organic solvent at elevated temperatures. Herein, we report that tetrahydrocarbazoles (THCs) are accessible by mechanochemical FI at ambient temperature. Using phenylhydrazine hydrochlorides in the presence of silica is critical for this solid-state variant of the FI.
A general synthetic route to indolesfrom readily available anilines and epoxides by using ruthenium catalysis is described. This straightforward transformation allows a variety of indoles to be obtained in good yields by using [Ru3(CO)12]/1,1′‐bis(diphenylphosphino)ferrocene as the catalytic system. Water and hydrogen are formed as the only stoichiometric by‐products, making this process highly atom
Organocatalyzed Enantioselective Formal [4 + 2] Cycloaddition of 2,3-Disubstituted Indole and Methyl Vinyl Ketone
作者:Quan Cai、Shu-Li You
DOI:10.1021/ol301114z
日期:2012.6.15
A formal [4 + 2] cycloaddition of 2,3-disubstituted indoles with vinylmethylketone was realized in the presence of a catalytic amount of quinine-derived primary amine and pentafluorobenzoic acid. This method provides bridged-ring indoline scaffolds containing two quaternary carbon centers with excellent yields and enantioselectivity (up to 98% yield and 98% ee).
Carbazole derivatives and their use as neuropeptide y5 receptor ligands
申请人:——
公开号:US20040067999A1
公开(公告)日:2004-04-08
Compounds of formula (I): are described wherein R
1
-R
6
and m are as defined within. Processes for their preparation and their use as NPY 5 inhibitors is described.
Thiourea-Catalyzed Enantioselective Addition of Indoles to Pyrones: Alkaloid Cores with Quaternary Carbons
作者:Charles S. Yeung、Robert E. Ziegler、John A. Porco、Eric N. Jacobsen
DOI:10.1021/ja508523g
日期:2014.10.1
We report the development of a catalytic method for the enantioselective addition of indoles to pyrone-derived electrophiles. Arylpyrrolidino-derived thioureas catalyze the addition with high stereoselectivity in the presence of catalytic quantities of an achiral Bronsted acid. The indole-pyrone adducts feature a quaternary stereocenter and represent an unusual class of indolines bearing structural resemblance to the hybrid natural product pleiocarpamine.