Ruthenium( II )‐Catalyzed CH/NH Carbonylative Cyclization of 2‐Aryl Quinazolinones with Isocyanates as CO Surrogates

Iridium-Catalyzed Regioselective B(4)-Alkenylation and B(3,5)-Dialkenylation of o-Carboranes

Iridium(I)-catalyzed regioselective B(4)-alkenylation has been developed from o-carboranyl sulfoxonium ylides and alkynes through B(4)-H activation. The sequential B(4)- and B(6)-alkenylation afforded B(3,5)-dialkenylated o-carboranyl sulfoxonium ylides in one pot. Eventually, two alkenyl groups, the same or different, were introduced at positions 3 and 5 of the carborane. Sulfoxonium ylide used as a directing group remains available for further functionalization and is converted to B-alkenylated o-carboranyl trichloromethyl ketones.

Iridium(III)-Catalyzed C-H Cyclization of Sulfoximines with Diazo Meldrum's Acids for the Synthesis of Cyclic Sulfoximines

Iridium(III)-catalyzed C-H cyclization of sulfoximines with diazo Meldrum's acid provided cyclic sulfoximines with a carbonyl group in good to excellent yields. These compounds were easily converted into unsubstituted and arylated sulfoximines. Moreover, the vinyl triflates obtained from the cyclic sulfoximines underwent palladium(II)-catalyzed cross-coupling reactions with a variety of aryl, arylalkynyl, and heteroatom (N and S) nucleophiles, affording a wide range of monosubstituted sulfoximines in high yields.

Iridium(III)-Catalyzed Regioselective B(4)-H Amination of o-Carboranes with Sufilimines

Iridium(III)-catalyzed regioselective B(4)-H amination is developed from the reaction of o-carborane acids with sulfilimines without any oxidants under mild conditions, which leads to a wide range of B(4)-H aminated o-carboranes in good yields with a broad substrate scope. Moreover, the selective B(3,6)-diamination reaction of the o-carborane acid was achieved. The present reaction is attractive from a practical point of view because dibenzothiophene is quantitatively recovered and reused.

Metal-Free N-H/C-H Carbonylation by Phenyl Isocyanate: Divergent Synthesis of Six-Membered N-Heterocycles

We disclose a method using phenyl isocyanate to synthesize carbonyl-containing N-heterocycles. The metal-free novel approach for both N-H and C-H carbonylation processes was successfully refined, delivering a range of synthetically valuable derivatives of quinazoline-2,4(1H,3H)-dione, 2H-benzo[e] [1,2,4] thiadiazin-3(4H)-one 1,1-dioxide, and pyrrolo[1,2-a] quinoxalin-4(5H)-one. The protocol features broad substrates with diverse reactions suitable for excellent yields, mild conditions, and good functional group compatibility. Moreover, the applicability of the reaction was characterized by gram-scale synthesis and synthetic transformations for drug molecules.

Alkali-modified heterogeneous Pd-catalyzed synthesis of acids, amides and esters from aryl halides using formic acid as the CO precursor

To establish an environmentally friendly green chemical process, we minimized and resolved a significant proportion of waste and hazards associated with conventional organic acids and molecular gases, such as carbon monoxide (CO). Herein, we report a facile and milder reaction procedure, using low temperatures/pressures and shorter reaction time for the carboxyl- and carbonylation of diverse arrays of aryl halides over a newly developed cationic Lewis-acid promoted Pd/Co₃O₄ catalyst. Furthermore, the reaction proceeded in the absence of acid co-catalysts, and anhydrides for CO release. Catalyst reusability was achieved via scalable, safer, and practical reactions that provided moderate to high yields, paving the way for developing a novel environmentally benign method for synthesizing carboxylic acids, amides, and esters.

To establish an environmentally friendly green chemical process, we minimized and resolved a significant proportion of waste and hazards associated with conventional organic acids and molecular gases, such as carbon monoxide (CO).