ORGN 781 |
| The emergence of pyrogallolarenes as potential aggregates for the design and synthesis of supramolecular capsules has recently been investigated. Syntheses of solvent-stabilized pyrogallolarene complexes derived from the condensation reaction of pyrogallol and alkyl aldehydes have been reported. Pyrogallolarenes derived from alkyl aldehydes under conditions of thermodynamic control lead to the rccc or cis ismomer (Scheme 1). Kinetic conditions, on the other hand, lead to the formation of the rctt or trans isomer. However, much less is known as to the geometry of pyrogallolarenes derived from aromatic aldehydes under similar reaction conditions and moreover, the self-assembled systems thereof. We wished to investigate this phenomenon fully by comparing the crystal structures of pyrogallolarene products derived from aromatic aldehydes under both conditions of thermodynamic and kinetic control. Interestingly, we have found that the geometry of product is independent of the reaction conditions and leads exclusively to the formation of the trans isomer.
Scheme 1. Synthesis of pyrogallolarenes
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Combinatorial, Parallel and Process Chemistry, Heterocycles, Aromatics, New Reactions and Methodology
8:00 PM-10:00 PM, Wednesday, August 22, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Organic Chemistry |
