| 摘要 |
Prepn. of an optically active N-acylated deriv. of proline (P) (acyl = ClCH2CO, n-butyryl, or isobutyryl), in which a supersatd. soln. of an N-acyl-DL-(P) (or unequal mixture of optical antipodes) is cooled, and pref. seeded (partic. for DL-racemate) to ppt. an N-acyl-L- or D-(P) (I). (I) may then be hydrolysed (process claimed) by known methods to L- or D- (P). Solvent pref. H2O, Me2CO, or MEK, partic. Me2CO for acyl = ClCH2CO and isobutyryl, and H2O for acyl = n-butyryl. Supersatd. soln. of (I) may be prepd. from a soln. of (I) by known methods (satd. temp. pref. 40 deg., and cooling rate pref. > 1 deg./hr). N-acyl-DL- (P) may be prepd. by known methods, incl. the racemization of the corresponding N-acyl-D-or L- (P) (by heat at > m.p. in presence of catalyst). |
