固体塩基触媒の最近の進歩

抄録

Certain types of metal oxides such as MgO, CaO, SrO, BaO, La₂O₃, CeO₂, Y₂O₃, ThO₂, ZrO₂, and ZnO act as solid base catalysts for several types of reactions. This review describes the generation of the basic sites on thier surfaces, the catalytic characteristics in the reactions, and the structure of active sites.
For generation of the basic sites, pretreatment of the metal oxides at elevated temperatures is required to remove strongly adsorbed H₂O, CO₂, and O₂ from the surfaces.
The catalytic behaviors of the solid base catalysts for the following reactions are explained ; double bond migration of olefins, alkynes, allenes, allylamines, and allyl ethers, hydrogenation of olefins, addition of amines to conjugated dienes, dehydrogenation and dehydration of alcohols, dehydrogenation and deamination of amines, dehydrogen halide of halogen compouds, alkylation of phenol, N-methylation of aniline, esterification of benzaldehyde, decomposition of diacetone alcohol, H₂-D₂ equilibration, and D exchange of olefins.
A plausible structure of catalytically active sites is presented as surface cation-anion pairs in low coordinations.