A transition-metal-free intramolecular dehydrohalide coupling via intramolecular homolytic aromatic substitution (HAS) with aryl radicals has been developed in the presence of potassium tert-butoxide and an organic molecule as the catalyst. The methodology has been applied to a concise synthesis of Amaryllidaceae alkaloids viz. oxoassoanine (1b), anhydrolycorinone (1d), and other related structures. Interestingly, the method also works only in the presence of potassium tert-butoxide.

A Lewis acid catalyzed Friedel-Crafts reaction of electron rich aromatics with 3-alkyl-3-hydroxy-2-oxindole (5) has been developed. The methodology provides a straightforward access to the core of azonazine (2) sharing an all-carbon quaternary stereocenter at the tetracyclic ring junction.

A Lewis acid catalyzed reaction of in situ generated 2H-indol-2-one () with various 2π and other electron-rich substrates has been developed. A variety of electron-rich substrates such as allyl/methallyltrimethylsilane, phenylacetylene, styrenes, acetophenone, and indoles have been used. The methodology provides a straightforward approach for the synthesis of 2-oxindoles with an all-carbon quaternary center at the pseudobenzylic position.

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.

We describe a highly enantioselective Diels–Alder reaction of cross‐conjugated cyclohexadienones with cyclopentadiene, in which five stereocenters are effectively controlled by a strongly acidic and confined imidodiphosphorimidate catalyst. Our approach provides tricyclic products in excellent stereoselectivity. We also report methods to convert the obtained products into useful intermediates and a computational study that aids in gaining deeper insight into the reaction mechanism and origin of stereoselectivity.