摘要：

This investigation has demonstrated the feasibility of using differences between the ultraviolet absorption spectra of certain diastereomerically related compounds to determine the relative configurations of the asymmetric carbon atoms involved. The four stereoisomers of Compound VIII have been prepared, and the configurations of the two asymmetric carbon atoms in each have been related to D-glyceraldehyde by chemical transformations. Comparisons of the spectra of the diastereomers of VIII, and of model compounds and VIII indicate that different degrees of steric inhibition of resonance exist in the diastereomers. The direction of this difference is in agreement with the direction predicted from a comparison of molecular models of the diastereomers. The relative rates of the reaction of the enantiomers of 2-s-butyl-4,6-dinitrochlorobenzene with (+)-α-phenylethylainine to form diastereomers of VIII have determined. The qualitative relationship between these rates has been correlated with the differences in spectra in the products, and the differences in the steric situations found in hypothetical models for the diastereomerically related transition states for the two reactions.

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