Completely N[superscript 1]-Selective Palladium- Catalyzed Arylation of Unsymmetric Imidazoles: Application to the Synthesis of Nilotinib
نویسندگان
چکیده
The completely N1-selective Pd-catalyzed arylation of unsymmetric imidazoles with aryl halides and triflates is described. This study showed that imidazoles have a strong inhibitory effect on the in situ formation of catalytically-active Pd(0)-ligand complex. The efficacy of the N-arylation reaction was improved drastically by the use of pre-activated solution of Pd2(dba)3 and L1. From these findings it is clear that while imidazoles can prevent binding of L1 to the Pd, once the ligand is bound to the metal, these heterocycles do not displace it. The utility of the present catalytic system was demonstrated by the regioselective synthesis of clinically important tyrosine kinase inhibitor nilotinib.
منابع مشابه
Synthesis of C₂-Symmetric Benzimidazolium Salts and Their Application in Palladium-Catalyzed Enantioselective Intramolecular α-Arylation of Amides.
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