Nickel-Catalyzed Electroreductive Coupling of Alkylpyridinium Salts and Aryl Halides
Jiantao Fu1, Windsor Lundy2, Rajdip Chowdhury3
1Discovery Chemistry, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States.
Abstract:
An electrochemical, nickel-catalyzed reductive coupling of alkylpyridinium salts and aryl halides is reported. High-throughput experimentation (HTE) was employed for rapid reaction optimization and evaluation of a broad scope of pharmaceutically relevant structurally diverse aryl halides, including complex drug-like substrates. In addition, the transformation is compatible with both primary and secondary alkylpyridinium salts with distinct conditions. Mechanistic insights were critical to enhance the efficiency of coupling using secondary alkylpyridinium salts. Systematic comparisons of the electrochemical and non-electrochemical methods revealed the complementary scope and efficiency of the two approaches.
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