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Rh(III)-catalyzed cyclopropanation initiated by C-H activation: ligand development enables a diastereoselective [2 + 1] annulation of N-enoxyphthalimides and alkenes.

ABSTRACT: N-Enoxyphthalimides undergo a Rh(III)-catalyzed C-H activation initiated cyclopropanation of electron deficient alkenes. The reaction is proposed to proceed via a directed activation of the olefinic C-H bond followed by two migratory insertions, first across the electron-deficient alkene and then by cyclization back onto the enol moiety. A newly designed isopropylcyclopentadienyl ligand drastically improves yield and diastereoselectivity.

SUBMITTER: Piou T

PROVIDER: S-EPMC4140504 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Rh(III)-catalyzed cyclopropanation initiated by C-H activation: ligand development enables a diastereoselective [2 + 1] annulation of N-enoxyphthalimides and alkenes.

Piou Tiffany T Rovis Tomislav T

Journal of the American Chemical Society 20140805 32

N-Enoxyphthalimides undergo a Rh(III)-catalyzed C-H activation initiated cyclopropanation of electron deficient alkenes. The reaction is proposed to proceed via a directed activation of the olefinic C-H bond followed by two migratory insertions, first across the electron-deficient alkene and then by cyclization back onto the enol moiety. A newly designed isopropylcyclopentadienyl ligand drastically improves yield and diastereoselectivity. ...[more]

PMID: 25093811

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