Catalytic hydrodefluorination of fluoroaromatics with silanes as hydrogen source at a binuclear rhodium complex: Characterization of key intermediates
作者:Lada Zámostná、Mike Ahrens、Thomas Braun
DOI:10.1016/j.jfluchem.2013.05.021
日期:2013.11
Stoichiometric and catalytic hydrodefluorination reactions of fluorinated aromatic substrates on using [Rh(μ-H)(dippp)]2 (1) (dippp = 1,3-bis(diisopropylphosphino)propane) as catalyst and HSiEt3 as a hydrogen source are reported. Treatment of the hydrido complex 1 with the fluoroarenes gave the fluorido complex [Rh(μ-F)(dippp)]2 (2) and organic hydrodefluorination products. An unusual ortho-selectivity
报道了使用[Rh(μ- H)(dippp)] 2(1)(dippp = 1,3-双(二异丙基膦基)丙烷)作为催化剂和HSiEt 3作为氢源的氟化芳族底物的化学计量和催化加氢脱氟反应。。用氟代芳烃处理氢化物络合物1,得到了氟化物络合物[Rh(μ- F)(dippp)] 2(2)和有机加氢氟化产物。在2,3,5,6-四氟吡啶和五氟苯的反应中观察到异常的邻位选择性,得到1,2-氢脱氟产物。配合物2的双核结构通过X射线衍射确认为固态。所述fluorido复杂2与HSiEt反应3和HSI我镨3通过消除对应的氟硅烷,得到η 2 -硅烷氢基络合物的[Rh(H)(η 2 -HSiEt 3)(dippp)](3)和[铑(H)(η 2 -HSi我镨3)(dippp)](4)表示。配合物3和4的结构由NMR数据和DFT计算得出。在5 mol%的1存在下,五氟吡啶,2,3,5,6-四氟吡啶或2,3,5,6-四氟吡啶,六氟和五氟苯与HSiEt