| 摘要 |
1496996 Preparing 1,5- and 1,8-dinitronaphthalenes BAYER AG 14 April 1976 [19 April 1975] 15272/76 Heading C2C The invention comprises a process for isolating 1,5- and 1,8-dinitronaphthalenes from a mixture of dinitronaphthalenes which contains at least said 1,5- and 1,8-isomers in which the mixture is treated first with a more polar solvent for dinitronaphthalenes to dissolve all the isomers except the 1,5-dinitronaphthalene which is recovered, the solution of isomers is then treated, after removal of the solvent therefrom, at elevated temperature with a less polar aromatic solvent for dinitronaphthalenes so as to dissolve all materials other than 1,8-dinitronaphthalene which is thus recovered, the more polar solvent being employed in an amount of 1À2 to 20 times the weight of 1,8-isomer in the mixture and the less polar solvent in an amount of 1 to 20 times the weight of said 1,8-isomer.
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