An Efficient Synthesis of Pyrrolocoumarins and Pyrroloquinolones by Acid-Catalysed Cyclisation of Acetylenic Amines in Water
作者:K. Majumdar、Sudipta Ponra、Somjit Hazra、B. Roy
DOI:10.1055/s-0030-1259990
日期:2011.5
A simple H+-catalysed cyclisation of acetylenic amines for the synthesis of pyrrolocoumarins and pyrroloquinolones under conventional heating or microwave irradiation has been achieved. The reaction requires inexpensive catalyst and simple yet clean reaction conditions and offers potentially bioactive heterocycles in 82-95% yields. pyrrolocoumarin - pyrroloquinolone - Brønsted acid catalysis - intramolecular
A new strategy for the synthesis of coumarin- and quinolone-annulated pyrroles via Pd(0) mediated cross-coupling followed by Cu(I) catalyzed heteroannulation
作者:K.C. Majumdar、Shovan Mondal
DOI:10.1016/j.tetlet.2008.02.044
日期:2008.4
The sequential coupling and cyclization reactions between aryl halides and (trimethylsilyl) acetylene (TMSA) with concurrent elimination of the TMS substituent, allows a straightforward synthesis of substituted pyrano[3,2-e]indolone and pyrrolo[3,2-f]quinolone derivatives in excellent yields. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis of 3-iodopyrrolocoumarins via iodine-induced 5-endo-dig electrophilic cyclization
作者:K. C. Majumdar、Nirupam De、Biswajit Sinha、B. Roy
DOI:10.1007/s00706-011-0694-0
日期:2012.7
An efficient synthesis of 3-iodopyrrolocoumarins has been achieved by a simple and straightforward strategy involving palladium-copper-catalyzed Sonogashira coupling followed by iodocyclization at ambient temperature using molecular iodine as the electrophilic source. In addition, functionalization at the 3-position of the iodocyclized product is performed via Sonogashira reaction.