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Synthesis of 2-oxindoles via 'transition-metal-free' intramolecular dehydrogenative coupling (IDC) of sp(2) C-H and sp(3) C-H bonds.

ABSTRACT: The synthesis of a variety of 2-oxindoles bearing an all-carbon quaternary center at the pseudo benzylic position has been achieved via a 'transition-metal-free' intramolecular dehydrogenative coupling (IDC). The construction of 2-oxindole moieties was carried out through formation of carbon-carbon bonds using KOt-Bu-catalyzed one pot C-alkylation of ?-N-arylamido esters with alkyl halides followed by a dehydrogenative coupling. Experimental evidences indicated toward a radical-mediated path for this reaction.

SUBMITTER: Kumar N

PROVIDER: S-EPMC4979638 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Synthesis of 2-oxindoles via 'transition-metal-free' intramolecular dehydrogenative coupling (IDC) of sp(2) C-H and sp(3) C-H bonds.

Kumar Nivesh N Ghosh Santanu S Bhunia Subhajit S Bisai Alakesh A

Beilstein journal of organic chemistry 20160608

The synthesis of a variety of 2-oxindoles bearing an all-carbon quaternary center at the pseudo benzylic position has been achieved via a 'transition-metal-free' intramolecular dehydrogenative coupling (IDC). The construction of 2-oxindole moieties was carried out through formation of carbon-carbon bonds using KOt-Bu-catalyzed one pot C-alkylation of β-N-arylamido esters with alkyl halides followed by a dehydrogenative coupling. Experimental evidences indicated toward a radical-mediated path for ...[more]

PMID: 27559367

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