title: Intramolecular dehydrogenative coupling of sp2 C-H and sp3 C-H bonds: an expeditious route to 2-oxindoles.
abstract: 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.
authors.affiliation: Department of Chemistry, Indian Institute of Science Education and Research Bhopal, MP-462 023, India.
authors.forename: Santanu
authors.initials: S
authors.lastname: Ghosh
authors.forename: Subhadip
authors.initials: S
authors.lastname: De
authors.forename: Badrinath N
authors.initials: BN
authors.lastname: Kakde
authors.forename: Subhajit
authors.initials: S
authors.lastname: Bhunia
authors.forename: Amit
authors.initials: A
authors.lastname: Adhikary
authors.forename: Alakesh
authors.initials: A
authors.lastname: Bisai