Calmuschi Beatrice, Jonas Alexander Erik, Englert Ulli
Institute of Inorganic Chemistry, RWTH Aachen University, Prof.-Pirlet-Strasse 1, 52074, Germany.
Acta Crystallogr C. 2004 Jul;60(Pt 7):m320-3. doi: 10.1107/S0108270104010856. Epub 2004 Jun 22.
Complexes of the composition trans-[Pd(L)2(OAc)2] have been postulated as intermediates during cyclopalladation. The first structural characterization of such a precursor has now been achieved and its role in the reaction sequence has been established. Diacetato-kappa2O-bis[(S)-1-(4-fluorophenyl)ethylamine-kappaN]palladium(II), [Pd(O2CMe)2(4-FC6H3CHMeNH2)2] or [Pd(C2H3O2)2(C8H10FN)2], (I), was obtained from palladium(II) acetate and (S)-NH2CHMeC6H3F-4 in a 1:2 molar ratio. The intermediate was then reacted with additional palladium(II) acetate to give the acetate-bridged dinuclear complex di-mu-acetato-kappa4O:O'-bis[[(S)-2-(1-aminoethyl)-5-fluorophenyl-kappa2C1,N]palladium(II)] benzene hemisolvate, [Pd(4-FC6H3CHMeNH2)2(mu-O2CMe)]2.0.5C6H6 or [Pd2(C8H9FN)2(C2H3O2)2].0.5C6H6, (II).
组成式为反式 - [Pd(L)₂(OAc)₂] 的配合物被假定为环钯化过程中的中间体。现在已首次实现了对这种前体的结构表征，并确定了其在反应序列中的作用。二乙酸根 - κ²O - 双[(S) - 1 - (4 - 氟苯基)乙胺 - κN]钯(II)，[Pd(O₂CMe)₂(4 - FC₆H₃CHMeNH₂)₂] 或 [Pd(C₂H₃O₂)₂(C₈H₁₀FN)₂]，(I)，由乙酸钯(II)和 (S) - NH₂CHMeC₆H₃F - 4 以 1:2 的摩尔比制得。然后该中间体与额外的乙酸钯(II)反应，得到乙酸根桥连的双核配合物二 - μ - 乙酸根 - κ⁴O:O' - 双[[(S) - 2 - (1 - 氨基乙基) - 5 - 氟苯基 - κ²C₁,N]钯(II)] 苯半溶剂化物，[Pd(4 - FC₆H₃CHMeNH₂)₂(μ - O₂CMe)]₂·0.5C₆H₆ 或 [Pd₂(C₈H₉FN)₂(C₂H₃O₂)₂]·0.5C₆H₆，(II)。
