Switchable Metal Sites in Metal–Organic Framework MFM?300(Sc): Lewis Acid Catalysis Driven by Metal–Hemilabile Linker Bond Dynamics

Size-selective Lewis acid catalysis in a microporous metal-organic framework with exposed Mn2+ coordination sites.

Treatment of selected aldehydes and ketones with cyanotrimethylsilane in the presence of the microporous metal-organic framework Mn3[(Mn4Cl)3BTT8(CH3OH)10]2 (1, H3BTT = 1,3,5-benzenetristetrazol-5-yl) leads to rapid conversion to the corresponding cyanosilylated products. The transformation is catalyzed by coordinatively unsaturated Mn2+ ions that serve as Lewis acids and lead to conversion yie...

Internal Lewis Acid Assisted Single Hydrogen Bond Donor Catalysis

Recent progress in Lewis acid–Lewis base bifunctional asymmetric catalysis*

Two enantioselective cyanation reactions, the Strecker reaction of ketoimines and the Reissert reaction of pyridine derivatives, promoted by Lewis acid–Lewis base bifunctional asymmetric catalysts are described.

Novel Lewis acid catalysis in organic synthesis

Cationic zirconocene or hafnocene complexes serve as a novel class of Lewis acid with unique reactivities, which are to be exploited in organic synthesis. Four categories of reactivities are discussed, that is, (A) C-F bond activation/cleavage, (B) Coordinative activation of ether linkages, (C) Carbonyl activation, and (D) C-0 bond cleavage via zirconocene alkoxide. Introduction Lewis acid-prom...

Green Lewis acid catalysis in organic synthesis*

New types of Lewis acids as water-stable catalysts have been developed. Metal salts such as rare earth metal triflates can be used in carbon–carbon bond-forming reactions in aqueous media. These salts can be recovered after the reactions and reused. Furthermore, Lewis acid–surfactant-combined catalysts, which can be used for reactions in water without using any organic solvents, have been also ...