Nanorattles, comprised of a nanosphere inside a nanoshell, were employed as the next generation of plasmonic catalysts for oxidations promoted by activated O2 . After investigating how the presence of a nanosphere inside a nanoshell affected the electric-field enhancements in the nanorattle relative to a nanoshell and a nanosphere, the SPR-mediated oxidation of p-aminothiophenol (PATP) functionalized at their surface was investigated to benchmark how these different electric-field intensities affected the performances of Au@AgAu nanorattles, AgAu nanoshells and Au nanoparticles having similar sizes. The high performance of the nanorattles enabled the visible-light driven synthesis of azobenzene from aniline under ambient conditions. As the nanorattles allow the formation of electromagnetic hot spots without relying on the uncontrolled aggregation of nanostructures, it enables their application as catalysts in liquid phase under mild conditions using visible light as the main energy input.

A novel and highly efficient synthetic approach to pyrroloindolines has been developed. The process is based on tandem radical addition/cyclization with inexpensive iron catalyst. This method tolerates a wide range of N-methyl-N-arylacrylamides as well carbamoyl radicals, providing access to a variety of functionalized 3,3-disubstituted oxindoles, key intermediates for many bioactive pyrroloindolines such as (±)-esermethole, (±)-deoxyeseroline, and (±)-physovenol methyl ether.

Nanorattles,c omprised of an anosphere inside an anoshell, were employed as the next generation of plasmonic catalysts for oxidations promoted by activated O 2 . After investigating how the presence of an anosphere inside an anoshell affected the electric-field enhancements in the nanorattle relative to an anoshell and an anosphere,t he SPRmediated oxidation of p-aminothiophenol (PATP) functionalized at their surface was investigated to benchmark howt hese different electric-field intensities affected the performances of Au@AgAu nanorattles,A gAun anoshells and Au nanoparticles having similar sizes.T he high performance of the nanorattles enabled the visible-light driven synthesis of azobenzene from aniline under ambient conditions.A st he nanorattles allowt he formation of electromagnetic hot spots without relying on the uncontrolled aggregation of nanostructures,i t enables their application as catalysts in liquid phase under mild conditions using visible light as the main energy input.Oxidation reactions play ap ivotal role in industrial processes and academic research, [1][2][3] in which the activation of molecular oxygen (O 2 )a tt he catalyst surface represents apromising alternative to achieve high activities. [4][5][6] Interestingly,i th as been demonstrated that the surface plasmon resonance (SPR) excitation in silver (Ag) and gold (Au) nanostructures can generate activated O 2 at the metal surface. [7][8][9][10][11][12] This process occurs through the charge transfer of SPR-excited hot electrons to adsorbed O 2 molecules,allowing the use of visible-light to drive oxidation reactions. [7][8][9][10][11][12] Most studies on SPR-mediated transformations have focused on first-generation plasmonic catalysts,t hat is,c onventional Ag and Au nanoparticles such as quasi-spheres, cubes,wires,plates,among others. [7][8][9][10][11][12] Herein, we propose the utilization of metallic nanorattles,comprised of ananosphere inside of an anoshell, as the next generation of plasmonic catalysts towards SPR-mediated oxidations by taking advantage of the plasmon hybridization concept. [13,14] In nanorattles, plasmon hybridization between the nanoshell and nanosphere components can lead to much higher electric field (E-field) enhancements relative to its individual counterparts. [15][16][17] Nanorattles also enable the generation of electromagnetic hot spots in ac ontrollable manner without relying on the uncontrolled aggregation among individual nanostructures. [18,19] This is not possible in first-generation plasmonic catalysts,a nd aggregation leads to ad ecrease in surface area and thus catalytic performance.P reviously,h igh efficiencies towards SPR-mediated transformations were described at junctions between Ag nanocubes supported over Al 2 O 3 . [20] Although these junctions could present higher E-field enhancements relative to the nanorattles,t heir formation still relies on the uncontrolled aggregation and the synthesis of nanocubes is more complex relative to spherical nanoparticles.F inally,p rocedures for...

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