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Published on: November 30, 2022
Nickel-catalyzed borylation of halides and pseudohalides with tetrahydroxydiboron [B2(OH)4]
Gary A Molander1, Livia N Cavalcanti, Carolina García-García
1Roy and Diana Vagelos Laboratories and Penn/Merck Laboratory for High Throughput Experimentation, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA. gmolandr@sas.upenn.edu
Abstract:
Arylboronic acids are gaining increased importance as reagents and target structures in a variety of useful applications. Recently, the palladium-catalyzed synthesis of arylboronic acids employing the atom-economical tetrahydroxydiboron (BBA) reagent has been reported. The high cost associated with palladium, combined with several limitations of both palladium- and copper-catalyzed processes, prompted us to develop an alternative method. Thus, the nickel-catalyzed borylation of aryl and heteroaryl halides and pseudohalides using tetrahydroxydiboron (BBA) has been formulated. The reaction proved to be widely functional group tolerant and applicable to a number of heterocyclic systems. To the best of our knowledge, the examples presented here represent the only effective Ni-catalyzed Miyaura borylations conducted at room temperature.
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