Treatment of 1-aryl-2,5-diphenylpyrroles with lithium powder in tetrahydrofuran at 0 °C results in the generation of the corresponding aryllithium reagents through reductive C–N bond cleavage.
A straightforward highly efficient Paal–Knorr synthesis of pyrroles
作者:Bimal K. Banik、Indrani Banik、Mercy Renteria、Swapan K. Dasgupta
DOI:10.1016/j.tetlet.2005.02.103
日期:2005.4
A straightforward simple synthesis of substituted pyrroles using bismuth nitrate-catalyzed modified Paal–Knorr method has been accomplished with an excellent yield. This method produces pyrroles with multicyclic aromatic amines.
Conversion of pyrroles into bi-1,2,5-thiadiazoles: a new route to biheterocycles
作者:Xiao-Guang Duan、Charles W. Rees
DOI:10.1039/a704065b
日期:——
5-diphenylpyrrole also give 12, together with 3-(benzoyldichloromethyl)-4-phenyl-1,2,5-thiadiazole 21 in high combined yield. The formation of bi-1,2,5-thiadiazole 12 from N-alkylpyrroles represents a new dissection of the pyrrole ring and a new and very short route to an aromatic biheterocyclic system. Mechanisms which rationalise the different pathways observed are proposed for all of these reactions.
A general and practical synthetic method for aryl-substituted five-membered heterocycles has been developed. In the presence of KOH (30%), 1,4-diaryl-1,3-butadiynes undergo the cyclocondensation reaction with water, primary amines, and Na2S·9H2O in DMSO at 80 °C to afford 2,5-diarylfurans, 1,2,5-trisubstituted pyrroles, and 2,5-diarylthiophenes in good to high yields. Further studies have disclosed