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A Diverted Aerobic Heck Reaction Enables Selective 1,3-Diene and 1,3,5-Triene Synthesis through C-C Bond Scission.

ABSTRACT: Substituted 1,3-dienes are valuable synthetic intermediates used in myriad catalytic transformations, yet modern catalytic methods for their preparation in a highly modular fashion using simple precursors are relatively few. We report here an aerobic boron Heck reaction with cyclobutene that forms exclusively linear 1-aryl-1,3-dienes using (hetero)arylboronic acids, or 1,3,5-trienes using alkenylboronic acids, rather than typical Heck products (i.e., substituted cyclobutenes). Experimental and computational mechanistic data support a pericyclic mechanism for C-C bond cleavage that enables the cycloalkene to circumvent established limitations associated with diene reagents in Heck-type reactions.

SUBMITTER: McAlpine NJ

PROVIDER: S-EPMC6424333 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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A Diverted Aerobic Heck Reaction Enables Selective 1,3-Diene and 1,3,5-Triene Synthesis through C-C Bond Scission.

McAlpine Neil J NJ Wang Long L Carrow Brad P BP

Journal of the American Chemical Society 20181015 42

Substituted 1,3-dienes are valuable synthetic intermediates used in myriad catalytic transformations, yet modern catalytic methods for their preparation in a highly modular fashion using simple precursors are relatively few. We report here an aerobic boron Heck reaction with cyclobutene that forms exclusively linear 1-aryl-1,3-dienes using (hetero)arylboronic acids, or 1,3,5-trienes using alkenylboronic acids, rather than typical Heck products (i.e., substituted cyclobutenes). Experimental and c ...[more]

PMID: 30289691

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