A Study of Negishi Cross-Coupling Reactions with Benzylzinc Halides To Prepare Original 3-Ethoxypyrazoles

Eloi P. Coutant (1) , Yves Louis Janin (1)

1 Chimie et Biocatalyse

The Negishi palladium-catalyzed cross-coupling reaction between 3-ethoxy-4-iodo-1H-pyrazole and various benzylzinc halides was extensively studied. Using simplified, robust, and optimized reaction conditions, a series of electron-poor benzylzinc halides were prepared and used to synthesize 4-benzyl-3-ethoxy-1H-pyrazoles derivatives. From these, iodination on C5 of the pyrazole nucleus led to the corresponding 4-benzyl-3-ethoxy-5-iodo-1H-pyrazoles, these are original building blocks for the preparation of libraries of new chemical entities

Domaines: Chimie organique

Eloi P. Coutant, Yves Louis Janin. A Study of Negishi Cross-Coupling Reactions with Benzylzinc Halides To Prepare Original 3-Ethoxypyrazoles. Synthesis: Journal of Synthetic Organic Chemistry, 2015, 47 (4), pp.511-516. ⟨10.1055/s-0034-1379458⟩. ⟨pasteur-01111917⟩