Cyclometalated Half-Sandwich Ruthenium Complexes: Preparation, Structure, and Catalytic Synthesis of Phenolic Esters from Aryl Halides without Using External CO under Air.

A series of cyclometalated C,N-chelate half-sandwich ruthenium complexes based on N-heterocyclic ligands were prepared through a simple route with good yields. These air- and moisture-stable cyclometalated ruthenium complexes showed excellent catalytic efficiency in phenoxy carbonylation of aryl halides with phenyl formate derivatives as a CO source and phenol as a coupling partner under air. Ester products were obtained with high yields at room temperature and without the need for an inert atmosphere.

Half-Sandwich Iridium Complexes Based on β-Ketoamino Ligands: Preparation, Structure, and Catalytic Activity in Amide Synthesis.

A series of β-ketoamino-based N,O-chelate half-sandwich iridium complexes with the general formula [Cp*IrClL] have been prepared in good yields. These air-insensitive iridium complexes showed desirable catalytic activity in an amide preparation under mild conditions. A number of amides with diverse substituted groups were furnished in a one-pot reaction with good-to-excellent yields through an amidation reaction of NHOH·HCl with aldehydes in the presence of these iridium(III) precursors.