Palladium-catalyzed asymmetric allylic substitutions in the presence of chiral phosphine-imine type ligands

Recent Advances in Enantioselective Pd-Catalyzed Allylic Substitution: From Design to Applications

This Review compiles the evolution, mechanistic understanding, and more recent advances in enantioselective Pd-catalyzed allylic substitution and decarboxylative and oxidative allylic substitutions. For each reaction, the catalytic data, as well as examples of their application to the synthesis of more complex molecules, are collected. Sections in which we discuss key mechanistic aspects for high selectivity and a comparison with other metals (with advantages and disadvantages) are also included. For Pd-catalyzed asymmetric allylic substitution, the catalytic data are grouped according to the type of nucleophile employed. Because of the prominent position of the use of stabilized carbon nucleophiles and heteronucleophiles, many chiral ligands have been developed. To better compare the results, they are presented grouped by ligand types. Pd-catalyzed asymmetric decarboxylative reactions are mainly promoted by PHOX or Trost ligands, which justifies organizing this section in chronological order. For asymmetric oxidative allylic substitution the results are grouped according to the type of nucleophile used.

Multifunctional chiral aminophosphines for enantiodivergent catalysis in a palladium-catalyzed allylic alkylation reaction

Trifunctional MAP-based chiral phosphines were tested as new ligands in a Pd-catalyzed asymmetric allylic alkylation, demonstrating fast and enantiodivergent catalysis. The palladium complexes of representative ligands by X-ray analysis revealed a novel mode of P,N-coordination of the ligand to the palladium center, which may contribute to switching the sense of the asymmetric induction via combined steric and tunable H-bonding interactions between the metal complex and the substrates.

A multisite-functionalised polymer for the extraction of thorium(iv) from water

A multisite functionalised polymer (MFP-1) was synthesized and applied in the effective extraction of thorium (Th(iv)) ions from water, which exhibits a maximum Th(iv) sorption capacity of 0.39 mmol g⁻¹ at 298 K and pH 3.8.

Palladium-catalyzed asymmetric [3+2] cycloaddition to construct 1,3-indandione and oxindole-fused spiropyrazolidine scaffolds

A facile and versatile Pd/L8-catalyzed asymmetric [3+2] cycloaddition of 3-diazooxindoles with a new vinylcyclopropane to construct spiropyrazolidine derivatives has been developed.

Highly chemoselective metal-free reduction of phosphine oxides to phosphines

Unprecedented chemoselective reductions of phosphine oxides to phosphines proceed smoothly in the presence of catalytic amounts of specific Brønsted acids. By utilizing inexpensive silanes, e.g., PMHS or (EtO)(2)MeSiH, other reducible functional groups such as ketones, aldehydes, olefins, nitriles, and esters are well-tolerated under optimized conditions.