INOR 657 |
| The neutral, diamagnetic, square planar Ni(II), Pd(II), and Pt(II) complexes of meso-tetraarylporphyrins have found numerous uses. For instance, Ni(II) is a popular protecting group for porphyrin transformations and the luminescence properties of the Pd(II) and Pt(II) porphyrins are utilized in oxygen sensing applications. The standard insertion conditions of Ni(II) into free base porphyrins using Ni(II) acetate are relatively harsh, i.e. reflux in pyridine for 24 h or reflux in DMF for several hours. The insertion of Pd(II) and Pt(II) even requires refluxing PhCN for extended periods of time. These conditions prevent, for instance, the insertion of the Pd(II) and Pt(II) into more sensitive porphyrin derivatives such as meso-tetraphenyl-2,3-dihydroxychlorin without decomposition of the ligand. Here we will report on the scope and limitations of the microwave-promoted insertion of group 10 metal ions into a number of porphyrin and chlorin derivatives. New challenges emerge when using the microwave, such as the affinity of Pd(0) to plate the reaction vessel. Nonetheless, the group 10 ions can be inserted in high yields using microwave heating in much shorter times (minute scale), thus preventing, or reducing significantly, the decomposition seen conventionally. |
|
Characterization and Applications of Coordination Compounds
7:00 PM-10:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Inorganic Chemistry |