Aldehyde- and ketone-induced tandem decarboxylation-coupling (Csp(3)-Csp) of natural alpha-amino acids and alkynes.

An interesting aldehyde- and ketone-induced intermolecular tandem decarboxylation-coupling (Csp(3)-Csp) catalyzed by copper with use of natural alpha-amino acids as starting materials is developed under neutral conditions with the production of CO(2) and H(2)O as the only byproducts. Various functionalized nitrogen-containing compounds were obtained by this method. In these processes, interesting regioselectivites of the alkylation were observed, which has been rationalized by the relative stability of proposed resonance structures based on computation methods.

Palladium-catalyzed aryl C-H bonds activation/acetoxylation utilizing a bidentate system.

A palladium-catalyzed aryl C-H bonds activation/acetoxylation reaction utilizing a bidentate system has been explored. This transformation has been applied to a wide array of pyridine and 8-aminoquinoline derivatives and it exhibits excellent functional group tolerance.

One-pot synthesis of highly substituted aromatic amine derivatives via Pd-catalyzed aminobenzannulation reaction.

A novel and convenient Pd(0)-catalyzed carboannulation with propargylic compounds for the synthesis of highly substituted aromatic amine derivatives in a one-pot operation was developed. In this process, a significant breakthrough in aminobenzannulation is observed. Moreover, the reaction appears to be very general and suitable for a variety of amines.

A novel iron-catalyzed decarboxylative Csp3-Csp2 coupling of proline derivatives and naphthol.

A novel iron-catalyzed intermolecular decarboxylative Csp(3)-Csp(2) coupling reaction using proline derivatives as starting materials is developed. In this process, a series of potentially useful ligands (tertiary aminonaphthol) for catalysis was obtained.

Highly regio- and stereoselective synthesis of indene and benzo[b]furan derivatives via a Pd-catalyzed carboannulation of propargyl carbonates with nucleophiles.

A new and efficient synthesis of indene and benzo[b]furan derivatives has been achieved via Pd-catalyzed carboannulation of propargyl carbonates with nucleophiles in good to excellent yields with high regio- and stereoselectivity. A novel sequence of nucleophilic attack is observed, and a possible mechanism is proposed.

New insight into Ni(II)-catalyzed cyclization reactions of propargylic compounds with soft nucleophiles: novel indenes formation.

We have disclosed a very nice advance of nickel(II)-catalyzed carboannulation reactions. Highly substituted indene derivatives are readily prepared in moderate to excellent yields under very mild reaction conditions in air via a nickel(II)-catalyzed cyclization of propargylic compounds with soft nucleophiles.

Synthesis of fused polycycles from propargylic compounds with terminal alkynes via a palladium-catalyzed tandem C-H activation/biscyclization process.

Various benzo[b]fluorene and fluorene derivatives have been prepared from propargylic compounds with terminal alkynes through a novel palladium-catalyzed tandem biscyclization reaction. This reaction involved a sequence of carboannulation, coupling, C-H activation and C-C bond formation process. A plausible mechanism has been proposed that was consistent with the deuterium-labeling experiment.

Highly regioselective synthesis of indene derivatives including an allene functional group via Pd/C-catalyzed cyclization reaction in air.

Indene derivatives including an allene functional group are readily prepared in moderate to excellent yields with high regioselectivity under very mild reaction conditions by the Pd/C-catalyzed reaction of propargylic compounds. The resulting products can be further elaborated using Pd-catalyzed annulation reactions.

Palladium-catalyzed carboannulation of propargylic carbonates and nucleophiles to 2-substituted indenes.

A new and efficient synthesis of 2-substituted indenes has been achieved via palladium-catalyzed carboannulation of propargylic carbonates with nucleophiles in good to excellent yields. A variety of nucleophiles were tolerated in this reaction.

Highly regio- and stereoselective synthesis of indene derivatives via electrophilic cyclization.

[reaction: see text] Indene or naphthalene derivatives are readily prepared in moderate to excellent yields with high regio- and stereoselectivity under very mild reaction conditions by the reaction of acetylenic malonates and ketones with I2, ICl, or NIS. The resulting iodides can be further elaborated using palladium-catalyzed coupling reactions.

Highly regioselective synthesis of 2,3-disubstituted indenes via a novel palladium-catalyzed cyclization reaction of propargylic carbonates with carbon nucleophiles.

Palladium-catalyzed reaction of propargylic carbonates with carbon nucleophiles offers an efficient, direct route to highly substituted indenes. The reaction conditions and the scope of the process are examined, and a possible mechanism is proposed. [reaction: see text]

Synthesis of 2-substituted 3-aroylindenes via palladium-catalyzed carbonylative cyclization of diethyl 2-(2-(1-alkynyl)phenyl)malonates with aryl halides.

[reaction: see text] The palladium-catalyzed reaction of readily accessible diethyl 2-(2-(1-alkynyl)phenyl)malonates with aryl halides under a balloon pressure of CO produced 2-substitued 3-aroylindenes in good yields. The reaction is believed to proceed via cyclization of the alkyne containing a proximate nucleophilic center promoted by an acylpalladium complex.

Synthesis of indenes via palladium-catalyzed carboannulation of diethyl 2-(2-(1-alkynyl)phenyl)malonate and organic halides.

Highly substituted indenes have been prepared in good yields by the palladium-catalyzed carboannulation of diethyl 2-(2-(1-alkynyl)phenyl)malonate with aryl, benzylic, and alkenyl halides. The reaction conditions and the scope of the process were examined, and a possible mechanism is proposed.