New Pd-NHC complexes have been synthesized and employed for palladium-catalyzed direct arylation of pyrrole derivatives by using electron-deficient aryl chlorides as coupling partners. The desired coupling products were obtained in moderate to good yields by using 1 mol % of these air-stable palladium complexes. This is an advantage compared to the procedures employing air-sensitive phosphines, which have been previously shown to promote the coupling of aryl chlorides with heteroarenes.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3596014PMC
http://dx.doi.org/10.3762/bjoc.9.35DOI Listing

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