| 摘要 |
1,273,278. Separation of binary mixtures. FARBWERKE HOECHST A.G. 7 Nov., 1969 [7 Nov., 1968], No. 54707/69. Heading C2C. Components of a binary mixture (except a binary mixture forming mixed crystals and/or congruently or incongruently melting solid phases) having a minimum melting point in the range -100 to +150‹ C. and a composition falling between the extrapolated branches of the melting point curve, are separated by inoculating an homogeneous melt of the binary mixture with crystals of one of the components at a temperature which is in the range of from 0À05 to 15‹ C. below the eutectic temperature, allowing this component to selectively crystallize until the melt contains substantially less of this component than the eutectic mixture and separating the crystals from the melt. In examples (1) ortho and para chloronitrobenzene are separated from each other and (2) enantiomers of a #-lactam of formula where R 1 is alkyl C 1-5 , vinyl or phenyl, R 2 and R 3 are each hydrogen, methyl or together form an alkylene C 3-5 ring with the proviso that if R 1 =R 2 , R 3 is not hydrogen are separated from the racemic mixture.
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