Palladium-catalyzed cross-coupling of pyrrole anions with aryl chlorides, bromides, and iodides.
[reaction: see text] A general method for the conversion of pyrrole anions to 2-arylpyrroles has been developed. Using a palladium precatalyst and sterically demanding 2-(dialkylphosphino)biphenyl ligands, (pyrrolyl)zinc chloride may be cross-coupled with a wide range of aryl halides, including aryl chlorides and aryl bromides, at low catalyst loadings and under mild conditions. A high degree of steric hindrance is tolerated. Certain ring-substituted pyrrole anions have also been arylated with aryl bromide substrates.
Rieth
Ryan D
RD
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, USA.
Mankad
Neal P
NP
Calimano
Elisa
E
Sadighi
Joseph P
JP