Koichi Kanehira

Asymmetric hydrogenation of enol phosphinates catalyzed by a chiral ferrocenylphosphine-rhodium complex. Asymmetric synthesis of optically active secondary alkyl alcohols

Abstract Catalytic asymmetric synthesis of secondary alkyl alcohols (up to 78% ee) was accomplished by asymmetric hydrogenation of enol diphenylphosphinates, derived from prochiral ketones such as acetophenone, 3-methyl-2-butanone, and 2-octanone, in the presence of a cationic rhodium complex of ( R )-1-[( C )-1′,2-bis(diphenylphosphino)ferrocenyl]ethanol (BPPFOH).

Kinetic resolution of racemic Grignard reagents by nickel-catalyzed asymmetric Grignard cross-coupling

Abstract Racemic Grignard reagents, 2-phenylpropylmagnesium chloride and 2-norbornylmagnesium chloride were kinetically resolved by asymmetric cross-coupling with vinyl bromides in the presence of chiral phosphine-nickel catalysts to give optically active coupling products (~37% ee) and carboxylic acids after carbonation with carbon dioxide.

Intermolecular photoaddition involving 1,4-transfer of cyano group. 3 photoaddition of 2-cyanopyridine to olefins

Abstract Photoreaction of 2-cyanopyridine with 2-methyl-2-butene and cyclopentene provided the corresponding annelated ketones 2 and 3, respectively, whereas photoreaction with 1-trimethylsilyloxycyclopentene afforded the “ene” product 8.

Selective cleavage of polycyclic cyclopropanes by electrochemical oxidation

Abstract Anodic oxidation in acetic acid of polycyclic cyclopropanes, namely tricyclene, cyclofenchene, and longicyclene, followed by hydrolysis brought about stereo- and regioselective formation of the corresponding homoallylic alcohols as the main product in good yields.

Synthesis of Polyisoprenepolyols Having Multiple Tertiary Hydroxy Moieties Via Hydromagnesation

Abstract Synthesis of polyisoprenepolyols possessing multiple tertiary hydroxy moieties has been achieved efficiently by using hydromagnesation.

New chiral ligands designed for palladium-catalysed asymmetric allylic alkylation

New chiral phosphine ligands containing a chiral functional group remote from the phosphino-groups have been found to be effective in the palladium-catalysed reaction of allyl acetate with the enolate anion of 2-acetylcyclohexanone and give the allylated product in significant enantiomeric enrichment.