ORGN 715 |
| Heterocycles such as pyrroles are frequently used in drug development and materials science. The ability to impart the desired properties on these systems depends on the ease at which relevant substitutions may be made on the pyrrole nucleus. This talk will describe our development of a simple, efficient, and modular synthesis of pyrroles in one pot, directly from three readily available building blocks: imines, acid chlorides and alkynes. The reaction of imines, acid chlorides, alkynes, base, and isocyanides or phosphorous(III) derivatives leads to the formation of pyrroles in high yields. Mechanistic studies suggest that this chemistry proceeds via the generation of 1,3-dipolar heterocycles: Münchnone imines and oxazaphospholium ylides, respectively. The latter represent a new class of 1,3-dipolar heterocycles, and their unique structure and reactivity will be discussed. The modular nature these syntheses provide control over all five positions on the pyrrole nucleus by judicious choice of starting material substitutions.
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Heterocycles and Aromatics
8:00 AM-12:00 PM, Thursday, 1 September 2005 Washington DC Convention Center -- Ballroom B, Oral
Division of Organic Chemistry |
