Ligand-Accelerated Palladium(II)-Catalyzed Enantioselective Amination of C(sp2)-H Bonds
The first example of the Pd(II)-catalyzed enantioselective amination of aryl C-H bonds is reported. The key to the successful realization of this asymmetric catalytic transformation was the identification of mono-N-protected α-amino-O-methylhydroxamic acid (MPAHA) ligands, which promote reactivity under mild conditions and control enantioselectivity. The counteranions in the solvent medium, hexafluoroacetylacetate and acetate, were also found to play key roles in stereocontrol and reactivity enhancement.
Site-Selective Catalytic Carboxylation of Unsaturated Hydrocarbons with CO2 and Water
A catalytic protocol that reliably predicts and controls the site-selective incorporation of CO2 to a wide range of unsaturated hydrocarbons utilizing water as formal hydride source is described. This platform unlocks an opportunity to catalytically repurpose three abundant, orthogonal feedstocks under mild conditions.
CARBOXYLATION OF ALCOHOLS WITH CARBON MONOXIDE SUPERSATURATED IN STRONG ACID. FACILE SYNTHESIS OF 2,2-BIS(4-HALOPHENYL)ACETIC, -PROPIONIC, AND RELATED ACIDS
Using 97percent H2SO4 supersaturated with carbon monoxide, bis(4-halophenyl)methanols, 1,1-bis(4-halophenyl)ethanols and related alcohols were transformed to the carboxylic acids in 60-95percent yields.