Regioselective synthesis of 1,5-diaryl-1H-imidazoles by palladium-catalyzed direct arylation of 1-aryl-1H-imidazoles.
[reaction: see text] A variety of 1,5-diaryl-1H-imidazoles have been regioselectively synthesized by direct coupling of 1-aryl-1H-imidazoles with aryl iodides or bromides in DMF in the presence of CsF as the base and a catalyst precursor consisting of a mixture of Pd(OAc)2 and AsPh3. The data obtained in this synthetic study support a reaction mechanism involving an electrophilic attack of an arylpalladium(II) halide species onto the imidazole ring. Interestingly, some imidazole derivatives synthesized in this study have been found to exhibit significant cytotoxic activity against human tumor cell lines.
Bellina
Fabio
F
Dipartimento di Chimica e Chimica Industriale, University of Pisa, via Risorgimento 35, I-56126 Pisa, Italy. bellina@dcci.unipi.it
Cauteruccio
Silvia
S
Mannina
Luisa
L
Rossi
Renzo
R
Viel
Stéphane
S
D002384:Catalysis; D007093:Imidazoles / Q000138:chemical synthesis* / Q000737:chemistry; D010165:Palladium / Q000737:chemistry*
D007093:Imidazoles; D010165:Palladium