Access to (S)-2-Methyloxetane and the Precursor (S)-1,3-Butanediol of Hight Enantiomeric Purity
(S)-2-Methyloxetane (1) and its precursor (S)-1,3-butanediol (2) were prepared in low to moderate chemical yield with less than 0.5percent racemization from (S)-ethyl lactate (4) and from (2S,3S)-allothreonine (14b).For the first time the enantiomeric purities of both the starting material and the product (1) were carefully determined by high-precision capillary gas chromatography on optically active resolving stationary phases.The validity of the quadrant rule, correlating the relative configuration of alkyloxiranes with the order of elution from manganese(II) bis (3) by complexation gas chromatography, is also confirmed for 2-methyloxetane (1).