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Exclusive 5-exo-dig hydroarylation of o-alkynyl biaryls proceeding via C-H activation pathway.

ABSTRACT: The first example of the palladium-catalyzed exclusive 5-exo-dig hydroarylation of o-alkynyl biaryls has been demonstrated. In contrast to the reported earlier carbocyclizations proceeding via the Friedel-Crafts mechanism, this hydroarylation efficiently proceeds with electron-neutral and electron-deficient arenes, producing fluorene frameworks with defined stereochemistry of the double bond. On the basis of the high reactivity of electron-deficient arenes toward cyclization, high values of inter- and intramolecular kinetic isotope effects, and the exclusive cis-selectivity of cyclization, a mechanism involving a C-H activation motif has been proposed for this transformation.

SUBMITTER: Chernyak N

PROVIDER: S-EPMC3687218 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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Exclusive 5-exo-dig hydroarylation of o-alkynyl biaryls proceeding via C-H activation pathway.

Chernyak Natalia N Gevorgyan Vladimir V

Journal of the American Chemical Society 20080322 17

The first example of the palladium-catalyzed exclusive 5-exo-dig hydroarylation of o-alkynyl biaryls has been demonstrated. In contrast to the reported earlier carbocyclizations proceeding via the Friedel-Crafts mechanism, this hydroarylation efficiently proceeds with electron-neutral and electron-deficient arenes, producing fluorene frameworks with defined stereochemistry of the double bond. On the basis of the high reactivity of electron-deficient arenes toward cyclization, high values of inte ...[more]

PMID: 18357988

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