Atsushi Satsuma

We report herein the first general catalytic system for the direct synthesis of N‐substituted γ‐ and δ‐lactams by reductive amination/cyclization of keto acids (including levulinic acid) with nitriles and H₂ under mild conditions (7 bar H₂, 110 °C, solvent free). The most effective catalyst, Pt and MoO_x co‐loaded TiO₂ (Pt‐MoO_x/TiO₂), shows a wide substrate scope, high turnover number (TON), and good reusability.

To elucidate the reaction mechanism of NO–C₃H₆–CO–O₂ over NiFe₂O₄, we investigated the dynamics of the adsorbed and gaseous species during the reaction using operando Fourier transform infrared (FTIR). The NO reduction activity dependent on the C₃H₆ and CO concentrations suggested that NO is reduced by C₃H₆ under three-way catalytic conditions. From FTIR measurements and kinetic analysis, it was clarified that the acetate species reacted with NO–O₂ to form N₂ via NCO, and that the rate-limiting step of NO reduction was the reaction between CH₃COO^– and NO–O₂. The NO reduction mechanism of the three-way catalyst on NiFe₂O₄ is different to that on platinum-group metal catalysts, on which NO reduction proceeds through N–O cleavage.

To develop a platinum group metal (PGM)-free automotive three-way catalyst (TWC), we investigated the structure–activity relationship for Fe–Ni oxide catalysts and found NiFe ₂ O ₄ with a spinel structure is an active component of the three-way catalytic reaction (NO–C ₃ H ₆ –CO–O ₂ ).

A Pd/Co/Al₂O₃ catalyst prepared by a galvanic deposition method exhibited notable catalytic activity for methane combustion, due to the higher reducibility of PdO nanoparticles on CoO_x.

Acidic metal oxides, in particular Ta ₂ O ₅ , significantly enhanced the conversion of 5-hydroxymethylfurfural to a cyclopentanone derivative.

Au/TiO ₂ prepared by CO treatment showed high catalytic activity for CO oxidation due to twinned structure of Au nanoparticles.