Institute of Organic Chemistry of the Polish Academy of Sciences, Warsaw, Poland.
J Org Chem. 2009 Dec 18;74(24):9517-20. doi: 10.1021/jo902124c.
A methodology that affords N-alkyl-2-arylpyrroles and N-aryl-2-arylpyrroles via direct coupling from aryl iodides has been developed. After examining various reaction parameters: solvent, ratio of reagents, catalyst, base and additives the optimal conditions for the condensation were identified. Two crucial factors, (a) anhydrous DMSO as solvent and (b) 5 M excess of pyrrole counterpart, were found to strongly influence the reaction outcome. The conditions identified (PdCl(2)(PPh(3))(2), AgOAc, anhyd DMSO, KF, 100 degrees C, 5 h) resulted in the formation of 2-arylpyrroles in 14-80% yield. Furthermore, the synthesis is compatible with electron-withdrawing and electron-donating groups on the aryl moiety.
已经开发出一种通过芳基碘化物直接偶联得到 N-烷基-2-芳基吡咯和 N-芳基-2-芳基吡咯的方法。在考察了各种反应参数（溶剂、试剂比、催化剂、碱和添加剂）后，确定了缩合的最佳条件。发现了两个关键因素：(a) 无水 DMSO 作为溶剂和 (b) 吡咯部分的 5M 过量，对反应结果有强烈影响。确定的条件（PdCl(2)(PPh(3))(2)、AgOAc、无水 DMSO、KF、100 摄氏度、5 小时）导致 2-芳基吡咯以 14-80%的产率形成。此外，该合成与芳基部分的吸电子和供电子基团兼容。
