Nickel-Catalyzed Cross-Electrophile Reductive Couplings of Neopentyl Bromides with Aryl Bromides
Soumik Biswas1, Bo Qu1, Jean-Nicolas Desrosiers1
1Chemical Development, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, Connecticut 06877, United States.
Abstract:
5-Cyanoimidazole was identified as an inexpensive ligand for nickel-catalyzed cross-electrophile couplings by screening a diverse set of pharmaceutical compound library. A strategic screening approach led to the discovery of this novel ligand, which was successfully applied in the preparation of various alkylated arene products with good to high yields. Furthermore, the properties of this ligand allowed expanding the scope of reductive couplings to challenging substrates, such as sterically hindered neopentyl halides, which are known to generate motifs that are prevalent in biologically active molecules.
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