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Only a limited number of ligands have been successfully employed for the Ni-catalyzed asymmetric hydrovinylation reaction. Diarylphosphonites prepared from readily available carbohydrates in conjunction with a highly dissociated counterion ([3,5-(CF3)2-C6H3)4B]- or SbF6-) effect the hydrovinylation of 4-bromostyrene or 4-isobutylstyrene under ambient pressure of ethylene with the best overall selectivities reported to date for these important substrates. In a prototypical synthesis of a 2-arylpropionic acid, 3-(4-bromophenyl)-1-butene (prepared in 98% isolated yield and 89% ee from 4-bromostyrene) has been transformed into (R)-ibuprofen by Ni-catalyzed cross-coupling with i-BuMgBr, ozonolysis, and subsequent oxidation of the resulting aldehyde.

Enantioselective catalysts produce organic compounds in enantiomerically enriched form. They are highly efficient tools for the synthesis of biologically active materials, such as pharmaceuticals and crop-protection chemicals, in which enantiomeric purity can be critical. The design of chiral ligands is the key to developing new enantioselective catalysts. Three unusual families of ligands have been used to develop practical technology for enantioselective hydrocyanation of olefins, ring-opening of epoxides, and hydrogenation of various compounds.