Addition of free radicals to unsaturated systems. Part XXI. Reactions of 1H-pentafluoropropene with bromine, hydrogen bromide, and trifluoroiodomethane under free-radical conditions
作者:Robert N. Haszeldine、James R. McAllister、Anthony E. Tipping
DOI:10.1039/p19740001303
日期:——
1H-Pentafluoropropene, as a 95 : 5 mixture of cis- and trans-isomers, reacts with bromine in light to give a 75 : 25 mixture of the threo- and erythro-dibromides which on dehydrobromination affords a mixture of cis- and trans-1-bromo-1,2,3,3,3-pentafluoropropene. Photochemical reaction of the olefin with hydrogen bromide gives as the major products a mixture of erythro- and threo-1-bromo-1,2,3,3,3-pentafluoropropane
1 H-五氟丙烯,为95:5的顺式和反式异构体混合物,与溴在光下反应,生成75:25的苏式和赤二溴化物混合物,脱氢溴化后可得到顺式和反式混合物-1-溴-1,2,3,3,3-五氟丙烯。烯烃与溴化氢的光化学反应产生的主要产物是赤-和苏--1-溴-1,2,3,3,3,3-五氟丙烷和2-溴-1,1,1,2,3的混合物-五氟丙烷的比例为70:16。苏-加合物进行脱氢溴化反应生成顺式-和-的混合物反式-1 H-五氟丙烯; 其他两种异构体仅提供顺式烯烃。三氟碘甲烷在光化学或热条件下与烯烃反应,生成赤型和苏型-1,1,1,2,3,4,4,4-八氟-2-碘丁烷和1,1,1,2的混合物, 3-五氟-3-碘-2-三氟甲基丙烷的比例分别为56:40:4和50:43:7; 两个前加合物的加氢碘化分别产生反式-八氟丁-2-烯和顺式和反式烯烃的95:5混合物。