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P-Stereogenic chiral phosphine BI-BOP is employed for the first time as ligand to promote catalytic enantioselective synthesis of phosphoryl-substituted atropisomeric vinylarenes through a palladium−carbene pathway. This strategy utilizes 10 mol% palladium(II) acetate, 10 mol% phosphine ligand as well as a variety of N-tosylhydrazones and phosphoryl-substituted aryl bromides as the reaction partners. The desired axially chiral vinylarenes were isolated with up to 80% yield and 96:4 er, and can be further converted effectively and stereoselectively into dialkylphosphoryl-substituted atropisomeric arenes through a Grignard reaction. This protocol offers a general approach to synthesize phosphoryl-substituted atropisomeric vinylarenes with high enantiomeric purities. [ABSTRACT FROM AUTHOR]

A series of efficient ruthenium catalysts has been developed for the asymmetric hydrogenation and transfer hydrogenation of ketones with high reactivities and selectivities. The new chiral bisdihydrobenzooxaphosphole (BIBOP)/diamine-ruthenium complexes catalyzed the enantioselective hydrogenation of substrates such as aryl and heteroaryl cyclic and alkyl ketones with substrate/catalyst (S/C) ratios of up to 100,000. The opposite sense of enantioselectivity can be obtained by proper selection of a diamine with a given chirality of the phosphine. The usefulness of the new system has been demonstrated in the asymmetric hydrogenation of a complex synthetic intermediate towards cholesteryl ester transfer protein (CETP) inhibitors at S/C 20,000 on large-scale operation. [ABSTRACT FROM AUTHOR]

A mild and general procedure for reduction of primary, secondary, and tertiary amides using catalytic triruthenium dodecacarbonyl and 1,1,3,3-tetramethyldisiloxane as reductant is described. The reaction is tolerant of numerous functional groups, and the amine products can often be isolated by direct crystallization as hydrochloride salts. The catalyst and silane are commercially available, air stable, and inexpensive, making the procedure accessible for both laboratory and large-scale applications. [ABSTRACT FROM AUTHOR]