Novel preparation of 2,5-diarylpyrroles from aromatic nitriles with 3-arylpropylmagnesium bromides, 1,3-diiodo-5,5-dimethylhydantoin, and BuOK
作者:Momoko Nakamura、Kazuhiro Yoshida、Hideo Togo
DOI:10.1016/j.tet.2022.132709
日期:2022.4
Treatment of aromatic nitriles with 3-arylpropylmagnesium bromides under warming conditions and then water, followed by the reaction with DIH at room temperature under irradiation with a LED lamp and then with tBuOK gave 2,5-diarylpyrroles in moderate yields. The key step of the present method is the formation of N-iodo-2,5-diaryl-4,5-dihydropyrroles by the reaction of the formed imines with DIH, which
5(4H)-Oxazolones 1 and munchnones 3 are reacted with triphenylvinylphosphonium bromide 2a to give, through a cycloaddition reaction, pyrrole derivatives 4a-d and 7a-c unsubstituted at C-3 and C-4. The use of substituted vinylphosphonium salts 2b,c and dipoles 1 and 3 allows the isolation of 3-methylpyrroles 4e,f and 7d,e and 3-pyrrolecarboxylic acids 9a-c, respectively. The cycloaddition reactions proceed with high regioselectivity because of the positive interaction of phosphonium group of 2 and carbonyl group of dipoles 1 and 3. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.
KOBAYASHI, TOMOSHIGE;IINO, YUKIO;NITTA, MAKOTO, J. CHEM. SOC. JAP., CHEM. AND IND. CHEM.,(1987) N 7, 1237-1243