Water as a solvent: transition metal catalyzed dehydrogenation of alcohols going green

Abstract

The long-established practice of using organic solvents in synthetic chemistry is currently becoming a major focus for environmental alarms as many of the chemical wastes are generated in the form...

Transition‐Metal‐Catalyzed Direct Substitution of Alcohols in Aqueous Media

“…Therefore, great efforts were made to explore the possiblility of TM-catalyzed direct substitution of alcohols in aqueous media. [10] The seminal reports on palladium-catalyzed substitution of allylic esters in a two-phase aqueous-organic medium, suggested that the active π-allylic Pd species can be stale enough in water. [11] Afterwards, accompanied by the in-depth understanding of the stability and catalytic activity of TM active species in aqueous media, the alcohol-based Tsuji-Trost reaction in aqueous media developed rapidly in recent decade.…”

“…Development of an atom‐economical reaction in aqueous media is one of the most important goals of green organic synthesis. Therefore, great efforts were made to explore the possiblility of TM‐catalyzed direct substitution of alcohols in aqueous media [10] . The seminal reports on palladium‐catalyzed substitution of allylic esters in a two‐phase aqueous‐organic medium, suggested that the active π‐allylic Pd species can be stale enough in water [11] .…”

Novel cyano-activated Cu(ii) complexes of arylhydrazones of active methylene nitriles and their catalytic application for azide–alkyne cycloaddition in water and glycerol

“…In recent years, there has been growing interest in the use of water as a solvent for catalytic reactions due to its abundance, low cost, and environmentally friendly properties. [11][12][13] In some cases, catalytic conversions are often better in an aqueous medium than in pure organic solvents due to the unique features of water such as high dielectric constant, the ability to act as a nucleophile or a leaving group, and the ability to solubilize polar reactants and catalysts. [14][15][16][17][18] Although homogeneous CuAAC can proceed in aqueous medium, the presence of an organic co-solvent (e.g.…”

Cationic and Neutral PdII and PtII Pincer Complexes of Phosphinamino-Triazolyl-Pyridine [PN(H)N]: Pincer Ligand-Stabilized Palladium Nanoparticles and Their Catalytic Annulation of Internal Alkynes to Indenones

“…Late transition metal complexes of PNN and PNP type pincer ligands have proven widespread applications in synthesis, different types of bond activation, , and catalysis . Different types of PNN and PNP ligands used by various groups are shown in Figure .…”