457883-60-2Relevant academic research and scientific papers
Synthesis, structures, and properties of a series of four-, five-, and six-coordinate cobalt(III) triazacorrole complexes: The first examples of transition metal corrolazines
Ramdhanie, Bobby,Zakharov, Lev N.,Rheingold, Arnold L.,Goldberg, David P.
, p. 4105 - 4107 (2008/10/08)
The syntheses of the first transition metal corrolazine complexes, in which the meso carbon atoms of a corrole framework have been replaced by N atoms, are reported. Metalation of the corrolazine [(TBP)8CzH3] (TBP = 4-tert-butylphenyl) (1) with Co-(acac)2 gives [(TBP)8CzCOIII] (2) in good yield. Addition of PPh3 to 2 in pyridine results in the formation of [(TBP)8CzCoIII(PPh3)] (3), which was characterized by X-ray crystallography. Likewise, addition of an excess of pyridine to 2 in CH2Cl2 followed by slow diffusion of MeOH gives [(TBP)8CzCOIII(py)2] (4) as a crystalline solid, which was also characterized by X-ray crystallography. The crystal structures of 3 and 4 reveal that the corrolazine cavity is significantly smaller (～0.1 A) than their regular corrole analogues. Characterization of 2-4 by UV-vis spectroscopy reveals some interesting features in the absorption spectra of these compounds, including a dramatic red-shift of the Soret band. In addition, binding of pyridine to 2 was evaluated quantitatively by UV-vis titration, revealing a formation constant of β2 = 9.0 × 107 M-2, which is larger than any of the regular CoIII corrole analogues.
