Intramolecular dehydrogenative coupling of sp2 C-H and sp 3 C-H bonds: An expeditious route to 2-oxindoles

Article abstract of DOI:10.1021/ol302767w

An intramolecular-dehydrogenative-coupling (IDC) using "transition- metal-free" oxidation conditions has been achieved to synthesize a variety of 2-oxindoles bearing an all-carbon quaternary stereogenic center at the benzylic position. The methodology involves a one-pot C-alkylation of β-N-arylamido esters (3, 6) with alkyl halides using potassium tert-butoxide concomitant with a dehydrogenative coupling. A radical-mediated pathway has been tentatively proposed for the oxidative process.