ORGN 719 |
| Complementary reactions of a dipyrromethanemonocarbinol with a dipyrromethane leading to a 5-isocorrole were investigated. 5-Isocorrole (pseudocorrole) is a porphyrinic macrocycle possessing a sp3 hybridized meso-position and a direct bipyrrole linkage. Analytical-scale reactions were performed to explore the interplay of acid catalyst, acid concentration, and reaction time on the yield of 5-isocorrole and the product obtained from self-condensation of the dipyrromethanemonocarbinol (a porphyrin or a porphodimethene). Representative conditions were examined via time course experiments. The complementary reaction routes led to very different outcomes. One route provided the 5-isocorrole as the major macrocyclic product with only low levels of porphyrin (from self-condensation). In contrast, the complementary route predominately afforded a porphodimethene (from self-condensation) and little 5-isocorrole. The selection of reaction route can have a profound effect on the outcome of the reaction. Key to this work was the preparation of the required dipyrromethane species and the development of methodology for monitoring analytical-scale reactions. |
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Heterocycles and Aromatics, Asymmetric Reactions and Syntheses and Total Synthesis of Complex Molecules
7:00 PM-9:00 PM, Wednesday, August 19, 2009 Walter E. Washington Convention Center -- Ballroom C, Poster
Division of Organic Chemistry |