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Cobalt Catalyzed Reductive Spirocyclopropanation Reactions.

ABSTRACT: Cobalt pyridine-diimine (PDI) complexes catalyze the reductive spirocyclopropanation of terminal 1,3-dienes. gem-Dichlorocycloalkanes serve as carbene precursors and Zn is used as a terminal electron source. The reaction is effective for a range of gem-dichloro partners including those containing sulfur and nitrogen heterocycles. An example of an intramolecular Rh-catalyzed [5 + 2]-cycloaddition of a vinyl spirocyclopropane is demonstrated, providing rapid access to a complex tricyclic framework. Overall, this catalyst system is capable of suppressing the kinetically facile 1,2-hydride shift, which has hampered the development of Simmons-Smith reactions using Zn carbenoids possessing β-hydrogen atoms.

SUBMITTER: Werth J

PROVIDER: S-EPMC7665105 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Cobalt Catalyzed Reductive Spirocyclopropanation Reactions.

Werth Jacob J Berger Kristen K Uyeda Christopher C

Advanced synthesis & catalysis 20191106 2

Cobalt pyridine-diimine (PDI) complexes catalyze the reductive spirocyclopropanation of terminal 1,3-dienes. <i>gem</i>-Dichlorocycloalkanes serve as carbene precursors and Zn is used as a terminal electron source. The reaction is effective for a range of <i>gem</i>-dichloro partners including those containing sulfur and nitrogen heterocycles. An example of an intramolecular Rh-catalyzed [5 + 2]-cycloaddition of a vinyl spirocyclopropane is demonstrated, providing rapid access to a complex tricy ...[more]

PMID: 33192219

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