(R)-(-)-2-Aminobutane is a chiral amine plays an important role in pharmaceutical chemistry and in organic synthesis as chiral auxiliary, which is used to determine the enantiomeric excess (ee).
Purification Methods
Dry it over solid NaOH overnight and fractionate it through a short helices packed column. The L-hydrogen tartrate salt has m 139-140o (from H2O), the 1H2O has m 96o []D +18.1o (c 11, H2O), the hydrochloride has m 152o [ ] 21 -1.1o (c 13, H2O) and the benzoyl derivative crystallises from EtOH as needles with m 97o, [] 21 -34.9o (c 11, H2O). [Bruck et al. J Chem Soc 921 1956,Kjaer & Hansen Acta Chem Scand 11 898 1957.] [Beilstein 4 H 161, 4 I 372, 4 III 308, 4 IV 617.] The S -(+)-enantiomer has has same properties except for the optical rotation which has the opposite sign.
