Tadakatsu Hayase

Asymmetric synthesis of pyrimidyl alkanol without adding chiral substances by the addition of diisopropylzinc to pyrimidine-5-carbaldehyde in conjunction with asymmetric autocatalysis

Enantiomerically enriched pyrimidyl alkanol with either S or R configuration was obtained stochastically from the reaction between pyrimidine-5-carbaldehyde and diisopropylzinc without adding chiral substances in conjunction with subsequent asymmetric autocatalysis, leading to amplification of the enantiomeric excess.

One-pot asymmetric autocatalytic reaction with remarkable amplification of enantiomeric excess

Abstract A trace amount ( ca. 3 mg) of 2-methylpyrimidyl alkanol with only a slight enantiomeric excess (0.2 – 0.3% e.e.) was auto-multiplied with dramatic amplification of enantiomeric excess (up to ca. 90% e.e.) in one-pot asymmetric autocatalytic reaction using diisopropylzinc and 2-methylpyrimidine-5-carbaldehyde.

Enantioselective synthesis of chiral 5-carbamoyl-3-pyridyl alcohols by asymmetric autocatalytic reaction

Abstract A catalytic amount of a chiral zinc alkoxide of 5-carbamoyl-3-pyridyl alkyl alcohol catalyzes an enantioselective alkylation of 5-carbamoylpyridine-3-carbaldehyde by diisopropylzinc to afford itself in up to 86% e.e. with the same configuration as the catalyst. Enantioselectivity is dependent on the structure of substituents on the nitrogen atom of the amide.

Catalytic asymmetric synthesis of chiral diol, bis[2-(1-hydroxyalkyl)-phenyl]ether, an asymmetric autocatalytic reaction

Abstract Chiral diols, bis[2-(1-hydroxyalkyl)phenyl]ethers, with very high e.e.s are synthesized by catalytic enantioselective alkylation of bis(2-formylphenyl)ether. Zinc alkoxides of chiral diols were found to work as asymmetric autocatalysts in the reaction between bis(2-formylphenyl)ether and dialkylzincs.

Catalytic chirally self-replicating molecule. Asymmetric autocatalytic reaction of a zinc alkoxide of chiral 1-ferrocenyl-2-methylpropan-1-ol

Abstract Isopropylzinc alkoxide of 1-ferrocenyl-2-methylpropan-1-ol was found to be a catalytic chirally self-replicating molecule which produces itself with the same configuration from ferrocenyl aldehyde and diisopropylzinc with 35–39% e.e. in good yields.

Asymmetric synthesis of N-(Diphenylphosphinyl)-ferrocenylamine by the enantioselective alkylation of ferrocenylimine

Abstract Optically active N -(diphenylphosphinyl)ferrocenylamines with good to high e.e.s were obtained by the enantioselective addition of dialkylzines to ferrocenyl-diphenylphosphinylimine in the presence of chiral β-aminoalcohols. The subsequent hydrolysis afforded a chiral ferrocenylamine without racemization.

Asymmetric autocatalytic reaction of 3-quinolylalkanol with amplification of enantiomeric excess

The enantiomeric excess of a chiral 3-quinolylalkanol increases from 8.9 to 88.1% by a series of asymmetric autocatalytic alkylations of quinoline-3-carbaldehyde using diisopropylzinc.

Asymmetric synthesis of optically active fluorine-containing alcohols by the catalytic enantioselective alkylation of aldehydes

Abstract Optically active fluorine-containing alcohols with up to 97% enantiomeric excess were synthesized by the enantioselective addition of dialkylzincs to fluorine-containing aldehydes using chiral β-aminoalcohol catalysts such as N,N -dibutylnorephedrine (DBNE, 2d ), 2-morpholino-1-phenyl-1-propanol ( 2g , MOPEP) and diphenyl(1-methylpyrrolidin-2-yl)methanol ( 3 , DPMPM).

An enantioselective Baylis–Hillman reaction catalyzed by chiral phosphines under atmospheric pressure

2,2’-Bis(diphenylphosphino)-1,1’-binaphthyl (BINAP) catalyzes the enantioselective Baylis–Hillman reaction between pyrimidine- 5-carbaldehydes and acrylates to provide chiral α-methylene β-hydroxy esters in up to 44% ee under atmospheric pressure.

Highly enantioselective synthesis of a chiral 3-quinolylalkanol by an asymmetric autocatalytic reaction

A catalytic amount of a chiral zinc alkoxide of 2-methyl-1-(3-quinolyl)propan-1-ol catalyses the enantioselective alkylation of quinoline-3-carbaldehyde by diisopropylzinc to afford 2-methyl-1-(3-quinolyl)propan-1-ol with the same configuration in high ee (up to 94%).