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Research has been conducted on the pyphos, an optically active dihedral angle atropisomeric P,N ligand. The preparation of this ligand, the X-ray characterization of the rhodium-pyphos complex and pyphos application in the rhodium-catalyzed asymmetric hydraboration of vinylarenes are discussed.

A new approach is described for the biaryl syntheses by using DMEDA as the catalyst to promote the direct C-H arylation of unactivated benzene in the presence of potassium tert-butoxide. The new method has involved an aryl radical anion as an intermediate and the studies have provided an option toward establishing a new horizon for direct C-H/cross-coupling reactions.

Rhodium-catalyzed asymmetric 1,4-addition of arylboronic acids to [beta]-phthaliminoacrylate esters to obtain high yields of [beta]-aryl-[beta]-amino acid esters is reported. The reaction used a hydroxorhodium/chiral diene complex to yield esters with 96-99% enantioselectivity.

A simple one-pot assembly of the commercially available starting materials such as indoles, acid chlorides, and chlorophosphines were used to prepare a new class of indolylphosphine ligands. The ligand obtained with high diversification could be used for palladium-catalyzed Suzuki-Miyaura coupling reaction of aryl chlorides with arylboronic acids.

The application and reactivity of a family of indolyl phosphine ligands to Suzuki-Miyaura cross-coupling of aryl tosylates is described. The highly active system could also be adapted for other boron nucleophiles, including trifluloroborate salts and boronate esters.

A practical protocol for the synthesis of enantiopore, axially chiral diphosphine ligands is developed. The chiral-bridged diphosphine ligands were successfully prepared through highly diastereoselective Ullmann coupling and ring-closure processes.

A palladium-catalyzed monoselective C3 arylation of 2-oxindoles with aryl tosylates is described. With the Pd/CM-phos catalyst system, the corresponding 3-arylated oxindoles can be obtained in good to excellent yields (≤97%). The reaction conditions are mild (using 0.5 mol % Pd in general and KF as a base), and functional groups such as methyl ester, NH amido, and enolizable keto moieties are found to be compatible. [ABSTRACT FROM AUTHOR]

Research describing the chemical characteristics of the reactions pertaining to the arsination of catalytic solvent-free type is presented. Particular attention is given to syntheses of sryl arsines which have been functionalized.