Chiral amino alcohols derived from natural amino acids as chiral solvating agents for carboxylic acids

Several chiral amino alcohols have been synthesized conveniently and effectively. 1H NMR was utilized to investigate their enantiodiscriminating abilities. Chiral amino alcohols 2 and 4 were discovered as efficient CSAs for the determination of the enantiomeric compositions of chiral carboxylic acids. In particular, for the Ts-derivatives of amino acids studied herein, 4 could be used for the assignment of the absolute configurations of the Ts-derivatives of amino acids with a neutral side chain through the chemical shift non-equivalences of their NH (Ts) protons with certain confidence.

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(S)-2-(5-Bromo-2-dimethylamino-benzylamino)-1,1,3-triphenyl-propan1-1-olC30H31N2OBr[α]D20=-41.6 (c 0.44, CHCl3)Source of chirality: l-phenylalanineAbsolute configuration: (S)

(S,S)-2-{[(2-Dimethylamino-5-methylphenyl)-naphthalen-1-ylmethyl]amino}-1,1,3-triphenyl-propan-1-olC41H40N2O[α]D20=+42.8 (c 0.50, CHCl3)Source of chirality: l-phenylalanineAbsolute configuration: (S,S)

(S,R)-2-{[(2-Dimethylamino-5-methylphenyl)-naphthalen-1-ylmethyl]amino}-1,1,3-triphenyl-propan-1-olC41H40N2O[α]D20=-34.9 (c 0.47, CHCl3)Source of chirality: l-phenylalanineAbsolute configuration: (S,R)