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Palladium-catalyzed amination of unprotected five-membered heterocyclic bromides.

ABSTRACT: An efficient method for the palladium-catalyzed amination of unprotected bromoimidazoles and bromopyrazoles is presented. The transformation is facilitated by the use of our newly developed Pd precatalyst based on the bulky biarylphosphine ligand tBuBrettPhos (L4). The mild reaction conditions employed allow for the preparation of a broad scope of aminoimidazoles and aminopyrazoles in moderate to excellent yields.

SUBMITTER: Su M

PROVIDER: S-EPMC3983327 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Palladium-catalyzed amination of unprotected five-membered heterocyclic bromides.

Su Mingjuan M Hoshiya Naoyuki N Buchwald Stephen L SL

Organic letters 20140113 3

An efficient method for the palladium-catalyzed amination of unprotected bromoimidazoles and bromopyrazoles is presented. The transformation is facilitated by the use of our newly developed Pd precatalyst based on the bulky biarylphosphine ligand tBuBrettPhos (L4). The mild reaction conditions employed allow for the preparation of a broad scope of aminoimidazoles and aminopyrazoles in moderate to excellent yields. ...[more]

PMID: 24417224

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