标题：Selective C-F/C-H bond activation of fluoroarenes by cobalt complex supported with phosphine ligands
作者：Li, Junye; Zheng, Tingting; Sun, Hongjian; Xu, Wengang; Li, Xiaoyan
作者机构：[Li, Junye; Zheng, Tingting; Sun, Hongjian; Xu, Wengang; Li, Xiaoyan] Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Peoples R China.; [Zheng, T 更多
通讯作者地址：[Li, XY]Shandong Univ, Sch Chem & Chem Engn, Shanda Nanlu 27, Jinan 250100, Peoples R China.
摘要：The reactions of pentafluoropyridine C5NF5, hexafluorobenzene C6F6, and perfluoronaphthalene C10F8 with cobalt(0) complex, Co(PMe3)(4), were investigated. The Co(I) complexes (4-C5NF4)Co(PMe3)(3) (1), (C6F5)Co(PMe3)(3) (2), (C10F7)Co(PMe3)(3) (3), (4-C5NF4)Co(PMe3)(4) (4) and (C10F7)Co(PMe3)(4) (6) were obtained by selective activation of the C-F bonds. The reactions of 1 and 2 with CO afforded dicarbonyl cobalt(I) complexes (4-C5NF4)Co(CO)(2)(PMe3)(2) (7), (C6F5)Co(CO)(2)(PMe3)(2) (8). Under similar reaction conditions, 2 as a C-H bond activation product was obtained from the reaction of pentafluorobenzene, C6F5H, with Co(PMe3)(4). The byproducts, hydrodefluorination product 1,2,4,5-C6F4H2 and F2PMe3 from the reaction of C6F5H and Co(PMe3)(4) were also observed. The reaction mechanism of C6F5H with Co(PMe3)(4) is proposed and partly-experimentally verified. The reaction of C6F5H with Co(PMe3)(4) under 1 bar of CO at room temperature afforded hydrido dicarbonyl cobalt(II) complex (C6F5)Co(H)(CO)(2)(PMe3)(2) (11). Treatment of the mixtures of C6F5H/Co(PMe3)(4) with hexachlorobenzene, C6Cl6, resulted in (C6F5)CoCl(PMe3)(3) (12) via C-H bond cleavage with the hydrodechlorination product pentachlorobenzene, C6Cl5H, and 1,2,4,5-tetrachlorobenzene, C6Cl4H2. The structures of complexes 1, 2, 6, 7, 8, 11 and 12 were determined by X-ray diffraction.