An extremely efficient cobalt catalyst for the hydroboration of both vinylarenes and aliphatic α-olefins with pinacolborane is described, providing the anti-Markovnikov products with excellent regio- and chemoselectivity, broad functional-group tolerance, and high turnover numbers (up to 19,800). The alkene hydroboration route is further extended to a two-step, one-pot hydroboration and cross-coupling of alkylboronates with aryl chlorides.

We report the synthesis of cobalt complexes of novel iminopyridine-oxazoline (IPO) ligands and their application to the asymmetric hydroboration of 1,1-disubstituted aryl alkenes. The new catalysts afforded α-alkyl-β-pinacolatoboranes with exclusive regioselectivity in high yields with up to 99.5% ee. Furthermore, we have applied this method to an efficient synthesis of naproxen.

A series of iron complexes of chiral iminopyridine-oxazoline (IPO) ligands have been synthesized. The most sterically hindered iron catalyst exhibits excellent activity (up to 99% yield) and high enantioselectivity (up to 93% ee) in asymmetric hydrosilylation of aryl ketones.

Co-catalyzed sequential hydroborations of alkyl and aryl alkynes with pinacolborane produce 1,1-diboronate esters with high selectivity and yields.

We disclose the synthesis of a series of manganese complexes of chiral iminopyridine oxazoline ligands and their application in the first manganese-catalyzed asymmetric ketone hydrosilylations. The most sterically hindered manganese catalyst bearing two CH(Ph) 2 groups at the 2,6-ortho positions of the imino aryl ring and a t Bu group on the oxazoline ring furnishes the secondary alcohols in high enantioselectivities and yields.

We report an asymmetric homocoupling of ortho-(iodo)­aryl­phosphine oxides and ortho-(iodo)­aryl­phosphonates resulting in highly enantio­enriched axially chiral bisphosphine oxides and bisphosphonates. These products are readily converted to enantio­enriched biaryl bisphosphines without need for chiral auxiliaries or optical resolution. This provides a practical route for the development of previously uninvestigated atropo­selective biaryl bisphosphine ligands. The conditions have also proven effective for asymmetric dimerization of other, non-phosphorus-containing aryl halides.

The asymmetric hydrogenation of vinylsilanes catalyzed by a new C 1-symmetric phosphine–pyridine–oxazoline cobalt complex is described. The method provides an efficient approach to chiral tertiary silanes with enantioselectivities up to 99% ee. Furthermore, the o-methyl-substituted benzylic silane products undergo ruthenium-catalyzed dehydrogenative silylation to produce chiral benzosilolanes in high yields without racemization of the stereogenic center α to the quaternary Si atom.

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