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A modified procedure for the palladium catalyzed borylation/Suzuki-Miyaura cross-coupling of aryl and heteroaryl halides utilizing bis-boronic acid.

ABSTRACT: A modified Pd-catalyzed method of forming aryl- and heteroarylboron species and a two-step, one-pot borylation/Suzuki-Miyaura cross coupling using the atom economical tetrahydroxydiboron (bis-boronic acid, BBA) is reported. By using ethylene glycol as an additive, the new method results in increased yields, lower BBA loading, faster reaction times, and a broader reaction scope, including previously problematic substrates such as heterocycles.

SUBMITTER: Molander GA

PROVIDER: S-EPMC4525720 | BioStudies | 2015-01-01

REPOSITORIES: biostudies

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Palladium-catalyzed borylation of aryl and heteroaryl halides utilizing tetrakis(dimethylamino)diboron: one step greener.

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A new palladium precatalyst allows for the fast Suzuki-Miyaura coupling reactions of unstable polyfluorophenyl and 2-heteroaryl boronic acids.

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Nickel-catalyzed borylation of halides and pseudohalides with tetrahydroxydiboron [B2(OH)4].

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Project description:Conditions for the Suzuki-Miyaura coupling of lithium triisopropyl borates are reported, as well as a procedure for a one-pot lithiation, borylation, and subsequent Suzuki-Miyaura coupling of various heterocycles with aryl halides. These borate species are much more stable toward protodeboronation than the corresponding boronic acids and can conveniently be stored on benchtop at room temperature.

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2012-01-01 | S-EPMC3465529 | BioStudies

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Axial shielding of Pd(II) complexes enables perfect stereoretention in Suzuki-Miyaura cross-coupling of Csp3 boronic acids.

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2019-01-01 | S-EPMC6427018 | BioStudies

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