Do Sitting-Atop Metalloporphyrin Complexes Exist? Observation of N-H- - - Bonding in Arene Solvates of a Diprotonated Porphyrin Dicatio

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• 作者：J. Luis Gá ; rate-Morales ; Fook S. Tham ; Christopher A. Reed
• 刊名：Inorganic Chemistry
• 出版年：2007
• 出版时间：March 5, 2007
• 年：2007
• 卷：46
• 期：5
• 页码：1514 - 1516
• 全文大小：94K
• 年卷期：v.46,no.5(March 5, 2007)
• ISSN：1520-510X

文摘

The existence of sitting-atop metalloporphyrin complexes, theproposed intermediates in the metalation of free-base porphyrins,has been explored via the microscopic reverse reaction, i.e.,protonation of metalloporphyrins with a strong acid. The reactionof M(Tp-TP) (M = Zn, Cu, Ni; Tp-TP = dianion of tetra-p-tolylporphyrin) with mesitylenium carborane salts produced onlythe demetalated porphyrin in its diprotonated form, [H₄Tp-TP][carborane]₂ (carborane = CHB₁₁H₅Cl₆^-, CHB₁₁H₅Br₆^-, CHB₁₁Cl₁₁^-).In arene solvents, the H₄Tp-TP²⁺ dication shows an unusuallyupfield shifted ¹H NMR resonance at ca. -6 ppm, which X-raycrystallography reveals to arise from N-H- - - hydrogen bondingof the acidic protons to arene solvent molecules.