Reaction of sulphur tetrafluoride with trans-4,5-dibromo-cis-1,2-cyclohexanedicarboxylic anhydride. A route to 7,7,9,9-tetrafluoro-8-oxa-cis-bicyclo[4.3.0]non-3-ene
作者:Wojciech Dmowski、Ireneusz Nowak、Peter G. Jones、Holger Thönnessen
DOI:10.1016/0022-1139(95)03342-4
日期:1996.2
2-dibromo-cis-4,5-bis-(trifluoromethyl)cyclohexane (5). Dehalogenation of this mixture with zinc gave a mixture of 7,7,9,9-tetrafluoro-8-oxa-cis-bicyclo[4.3.0]non-3-ene (6) and cis-4,5-bis(trifluoro-methyl)cyclohex-1-ene (7). Pure 6 was isolated by bromination and subsequent separation of the dibromo derivatives by crystallization and debromination. The structure of isomer 3a was confirmed by X-ray analysis
用SF 4和HF处理反式-4,5-二溴-顺式-1,2-环己烷二羧酸酐(2)导致羰基氟化,几乎全部被氟取代一个溴原子,从而得到3-溴4 ,7,7,9,9-五氟-8-氧杂-顺式-双环[4.3.0]壬烷(3)和1-溴-2-氟-顺式-4,5-双(三氟甲基)环己烷(4)比例为5:1,仅含有痕量的1,2-二溴-顺式-4,5-双-(三氟甲基)环己烷(5)。用锌对该混合物脱卤,得到7,7,9,9-四氟-8-氧杂-顺-双环[4.3.0]非-3-烯的混合物(6)和顺式-4,5-双(三氟甲基)环己-1-烯(7)。通过溴化分离纯的6,随后通过结晶和脱溴分离二溴衍生物。异构体3a的结构通过X射线分析确认。