Palladium-catalyzed 2-arylation of pyrroles.


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.

DOI: 10.1021/jo902124c

Cite this paper

@article{Gryko2009Palladiumcatalyzed2O, title={Palladium-catalyzed 2-arylation of pyrroles.}, author={Daniel T Gryko and Olena Vakuliuk and Dorota Gryko and Beata Koszarna}, journal={The Journal of organic chemistry}, year={2009}, volume={74 24}, pages={9517-20} }