Direct Arylation of Pyrrole Derivatives in Ionic Liquids
作者:Olena Vakuliuk、Daniel T. Gryko
DOI:10.1002/ejoc.201100004
日期:2011.5
An efficient methodology for the directarylation of pyrrolederivatives has been developed. The reaction proceeds smoothly with a wide range of structurally diverse aryl iodides. Derivatives bearing an N,N-dimethylamino group at the 1-position and an aryl substituent at the 2-position were prepared for the first time. This protocol is more environmentally friendly than those previously reported because
作者:Daniel T. Gryko、Olena Vakuliuk、Dorota Gryko、Beata Koszarna
DOI:10.1021/jo902124c
日期:2009.12.18
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 (PdCl2(PPh3)(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.