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Catalytic Carbo- and Aminoboration of Alkenyl Carbonyl Compounds via Five- and Six-Membered Palladacycles.

ABSTRACT: A palladium(II)-catalyzed alkene difunctionalization reaction has been developed, wherein B2pin2 is used to trap chelation-stabilized alkylpalladium(II) intermediates that are formed upon nucleopalladation. A range of carbon and nitrogen nucleophiles were found to be suitable coupling partners in this transformation, providing moderate to high yields. Both 3-butenoic and 4-pentenoic acid derivatives were reactive substrate classes, affording ?,?- and ?,?-difunctionalized carboxylic acid derivatives. This work represents a new strategy to synthesize highly functionalized secondary boronates that complements existing methods.

SUBMITTER: Liu Z

PROVIDER: S-EPMC6002770 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Catalytic Carbo- and Aminoboration of Alkenyl Carbonyl Compounds via Five- and Six-Membered Palladacycles.

Liu Zhen Z Ni Hui-Qi HQ Zeng Tian T Engle Keary M KM

Journal of the American Chemical Society 20180207 9

A palladium(II)-catalyzed alkene difunctionalization reaction has been developed, wherein B<sub>2</sub>pin<sub>2</sub> is used to trap chelation-stabilized alkylpalladium(II) intermediates that are formed upon nucleopalladation. A range of carbon and nitrogen nucleophiles were found to be suitable coupling partners in this transformation, providing moderate to high yields. Both 3-butenoic and 4-pentenoic acid derivatives were reactive substrate classes, affording β,γ- and γ,δ-difunctionalized ca ...[more]

PMID: 29384373

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