A new protocol for the synthesis of 4,7,12,15-tetrachloro[2.2]paracyclophane
نویسندگان
چکیده
We report a green and convenient protocol to prepare 4,7,12,15-tetrachloro[2.2]paracyclophane, the precursor of parylene D, from 2,5-dichloro-p-xylene. In the first bromination step, with H2O2-HBr as a bromide source, this procedure becomes organic-waste-free and organic-solvent-free and can appropriately replace the existing bromination methods. The Winberg elimination-dimerization step, using aqueous sodium hydroxide solution instead of silver oxide for anion exchange, results in a significant improvement in product yield. Furthermore, four substituted [2.2]paracyclophanes were also prepared in this convenient way.
منابع مشابه
Two-photon absorption in three-dimensional chromophores based on [2.2]-paracyclophane.
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