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Palladium-catalyzed oxidative arylhalogenation of alkenes: synthetic scope and mechanistic insights.

ABSTRACT: This article describes the development of a Pd-catalyzed reaction for the arylhalogenation (halogen = Cl or Br) of diverse alpha-olefins by oxidatively intercepting Mizoroki-Heck intermediates. These transformations afford synthetically useful 1,2- and 1,1-arylhalogenated products in good yields with good to excellent selectivities that can be modulated by changing the nature of the halogenating reagent and/or the reaction conditions. The selectivity of these reactions can be rationally tuned by (i) controlling the relative rates of oxidative functionalization versus beta-hydride elimination from equilibrating Pd(II)-alkyl species and (ii) stabilization of organometallic Pd(II) intermediates through the formation of pi-benzyl adducts. These arylhalogenations exhibit modest to excellent levels of stereoselectivity, and the key carbon-halogen bond-forming step proceeds with predominant retention of stereochemistry at carbon.

SUBMITTER: Kalyani D

PROVIDER: S-EPMC2895562 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Palladium-catalyzed oxidative arylhalogenation of alkenes: synthetic scope and mechanistic insights.

Kalyani Dipannita D Satterfield Andrew D AD Sanford Melanie S MS

Journal of the American Chemical Society 20100601 24

This article describes the development of a Pd-catalyzed reaction for the arylhalogenation (halogen = Cl or Br) of diverse alpha-olefins by oxidatively intercepting Mizoroki-Heck intermediates. These transformations afford synthetically useful 1,2- and 1,1-arylhalogenated products in good yields with good to excellent selectivities that can be modulated by changing the nature of the halogenating reagent and/or the reaction conditions. The selectivity of these reactions can be rationally tuned by ...[more]

PMID: 20515033

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