Asymmetric addition of diethylzinc to aldehydes catalyzed by a camphor-derived β-amino alcohol

The asymmetric addition of diethylzinc to aromatic and aliphatic aldehydes, including linear aliphatic ones, catalyzed by 2 mol % of β-amino alcohol (1S, 2R)-7,7-dimethyl-1-morpholin-4-yl-bicyclo[2.2.1]heptan-2-ol 10 gave the corresponding secondary alcohols in high yields and with up to 94% ee at ambient temperature after 15 min.

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(1S)-7,7-Dimethyl-1-pyrrolidin-1-yl-bicyclo[2.2.1]heptan-2-oneC13H21NOEe = 100%[α]D24=+45.2 (c 1.0, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S)

(1S)-7,7-Dimethyl-1-piperidin-1-yl-bicyclo[2.2.1]heptan-2-oneC14H23NOEe = 100%[α]D24=+91.4 (c 1.0, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S)

(1S)-7,7-Dimethyl-1-morpholin-4-yl-bicyclo[2.2.1]heptan-2-oneC13H21NO2Ee = 100%[α]D24=+82.5 (c 1.0, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S)

(1S, 2R)-7,7-Dimethyl-1-pyrrolidin-1-yl-bicyclo[2.2.1]heptan-2-olC13H23NOEe = 100%[α]D24=+1.2 (c 1.0, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S, 2R)

(1S, 2R)-7,7-Dimethyl-1-piperidin-1-yl-bicyclo[2.2.1]heptan-2-olC14H25NOEe = 100%[α]D24=+14.2 (c 1.0, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S, 2R)

(1S, 2R)-7,7-Dimethyl-1-morpholin-4-yl-bicyclo[2.2.1]heptan-2-olC13H23NO2Ee = 100%[α]D24=+11.0 (c 1.0, CHCl3)Source of chirality: asymmetric synthesisAbsolute configuration: (1S, 2R)