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A palladium catalytic method has been developed for the coupling of amides and cyclopropanols to γ-diketones, through simultaneous C–N and C–C activation. Heteroatom ligand exchange and heteroatom-to-carbon ligation mode switching enable the achievement of molecular cross-coupling in an amide N-atom structural context-dependent manner, avoiding any stoichiometric organometallic reagent or base. [ABSTRACT FROM AUTHOR]

Uniformly distributed In2O3 nanoparticle modified reduced graphene oxide sheets (In2O3/rGO) were synthesized via a normal-pressure microwave-assisted method with an in situ growth process. In the In2O3/rGO composites, In2O3 nanoparticles with sizes ranging from 3 to 26 nm are evenly fixed on rGO surfaces. In2O3/rGO sensors exhibit high sensitivity, rapid response and recovery, and high selectivity toward 1–50 ppm NO gas at 150 °C. The mass ratio of indium nitrate to GO during synthesis (16–24) dramatically influences the NO-sensing properties of In2O3/rGO composites, and the 20-In2O3/rGO sensor shows the highest response at the optimal operating temperature of 150 °C. Compared with the In2O3 sensor, the 20-In2O3/rGO sensor presents greatly improved gas-sensing properties, including higher response, lower optimal operating temperature, and better selectivity toward NO gas. The response of the 20-In2O3/rGO sensor toward 50 ppm NO at 150 °C is 30.6, 6 times higher than that (5.2) of the In2O3 sensor. The enhanced NO-sensing properties of the In2O3/rGO nanocomposite could be attributed to the synergistic effect of In2O3 particles and rGO sheets. [ABSTRACT FROM AUTHOR]

Previous transition metal-catalyzed synthesis processes of δ-diketones are plagued by the high cost of the rhodium catalyst and harsh reaction conditions. Herein a low-cost, room temperature ruthenium catalytic method is developed based on the coupling of α-keto sulfoxonium ylides with cyclopropanols. The mild protocol features a broad substrate scope (47 examples) and a high product yield (up to 99%). Mechanistic studies argue against a radical pathway and support a cyclopropanol ring opening, sulfoxonium ylide-derived carbenoid formation, migratory insertion C–C bond formation pathway. [ABSTRACT FROM AUTHOR]