An N-bromosuccinimide-catalyzed intermolecular annulation of acetyl indoles with alkynes was developed, allowing for regioselective formation of valuable carbazoles through direct C–H bond functionalization. The readily available catalyst, wide substrate scope, gram scale synthesis, and mild conditions make this method practical. Mechanistic investigations indicate that the bromination of acetyl indole takes place to generate a bromide intermediate, followed by coupling with an alkyne and intramolecular cycloaromatization to furnish carbazole products.

Bromide-mediated intermolecular annulation of phenylethanone derivatives with alkynes has been developed, which allows for the regioselective formation of polysubstituted 1-naphthols. The usage of readily available bromine catalyst, broad substrate scope, and mild conditions make this protocol very practical. Mechanistic investigations reveal that the bromination of phenylethanone derivatives occurs to yield bromo-substituted intermediates, which react in situ with alkynes to furnish the desired 1-naphthols.

A metal-free iodine-catalyzed intramolecular amination has been developed for the practical synthesis of pyrrolo[2,3-b]indoles from readily available tryptophan esters. The transformation has been applied to a wide array of substrates and can be performed on gram scale under very mild conditions.

An efficient method for the synthesis of epoxides from carbonyl compounds, sulfoxides, and benzyne is presented. The strategy involved an epoxidation by a sulfur ylide which is formed in situ from sulfoxide and benzyne through the S–O bond insertion and deprotonation. This one-pot reaction proceeds under mild and base-free conditions, providing a convenient way to introduce the substituted methylene groups onto the carbonyl carbon.

A S–O bond insertion reaction of sulfoxides with arynes is reported. This reaction represents a rare instance of semipolar single bond insertion in aryne chemistry. The study of mechanism indicates that a sulfur ylide triggered by aryne is the key intermediate, which further transfers its methylene group to carbonyl compounds to give epoxides and thioethers through a sequential process.

An oxidative olefination reaction between aliphatic primary amines and benzylic sp3 C–H bonds has been achieved using N-bromosuccinimide as catalyst and tert-butyl hydroperoxide as oxidant. The olefination proceeds under mild metal-free conditions through direct deamination and benzylic C–H bond activation, and provides easy access to biologically active 2-styrylquinolines with (E)-configuration.

A metal-free Bu4NI mediated oxidative reaction utilizing tertiary aliphatic amines and 1,3-dicarbonyl compounds for the synthesis of methylene-bridged bis-1,3-dicarbonyl compounds has been developed. This reaction involved an unexpected C–C bond cleavage of tertiary aliphatic amines. With this approach, the completely regioselective functionalization of β-carbon on tertiary amines was realized.

An efficient and regioselective bromination of 2-aminopyridines was developed. The environmental friendly bromination occurs under mild and clean conditions using readily available 1-butylpyridinium bromide as the bromine source and hydrogen peroxide as the green oxidant.

An addition of benzylic sp3 C–H to electron-deficient olefins has been developed. This reaction provides a new method for the benzylic C–H bond functionalization of azaarenes without using any catalyst and additives.

An nBu4NI-catalyzed benzylic C–H acyloxylation of alkylarenes with readily available aromatic aldehydes has been developed. These reactions occur under mild and clean reaction conditions using tert-butyl hydroperoxide as the green terminal oxidant.

nBu4NI-catalyzed C3-selective formylation of N–H and N-substituted indoles by using N-methylaniline as a formylating reagent was first successfully demonstrated.

A one-pot dual functionalization of indoles has been developed. The simultaneous C3-formylation and N-aminomethylation of indoles can be achieved using readily available potassium iodide as a catalyst and tert-butyl peroxybenzoate as a co-oxidant.

A one-pot dual functionalization of indoles has been developed. The simultaneous C3-formylation and N-aminomethylation of indoles can be achieved using readily available potassium iodide as a catalyst and tert-butyl peroxybenzoate as a co-oxidant.

A metal-free iodine-catalyzed intramolecular amination has been developed for the practical synthesis of pyrrolo[2,3-b]indoles from readily available tryptophan esters. The transformation has been applied to a wide array of substrates and can be performed on gram scale under very mild conditions.

An nBu4NI-catalyzed benzylic C–H acyloxylation of alkylarenes with readily available aromatic aldehydes has been developed. These reactions occur under mild and clean reaction conditions using tert-butyl hydroperoxide as the green terminal oxidant.

nBu4NI-catalyzed C3-selective formylation of N–H and N-substituted indoles by using N-methylaniline as a formylating reagent was first successfully demonstrated.

An oxidative olefination reaction between aliphatic primary amines and benzylic sp3 C–H bonds has been achieved using N-bromosuccinimide as catalyst and tert-butyl hydroperoxide as oxidant. The olefination proceeds under mild metal-free conditions through direct deamination and benzylic C–H bond activation, and provides easy access to biologically active 2-styrylquinolines with (E)-configuration.