Syntheses and Bergman cyclization of highly conjugated arenediynes

ORGN 17

John D. Spence, jspence@csus.edu, Department of Chemistry, California State University Sacramento, 6000 J Street, Sacramento, CA 95819
The discovery that simplified arenediynes undergo photochemical Bergman cyclizations marked a significant advance in the development of enediyne pro-drugs. While enediynes contain two mutually perpendicular p-systems the majority of current models lack significant chromophores and require ultra-violet irradiation to promote cyclization. We have developed a program to synthesize highly conjugated arenediynes to examine the potential to employ visible light to trigger photocyclization. A series of aryl-fused quinoxalenediynes has been prepared from the condensation of aromatic 1,2-diones with a diaminoarenediyne to examine the effect of increased conjugation to the out-of-plane enediyne p-system. In a similar fashion, conjugation to the in-plane enediyne p-system has been accomplished by linking porphyrin or phenylethynyl groups to terminal arenediynes. In addition to providing extended conjugation these models introduce heteroaromatic scaffolds to pursue solubility and DNA binding upon N-alkylation. Our synthetic methods and ongoing studies towards Bergman cyclizations will be presented.
 

Heterocycles and Aromatics
8:00 AM-12:00 PM, Sunday, 26 March 2006 Georgia World Congress Center -- C301, Oral

Division of Organic Chemistry

The 231st ACS National Meeting, Atlanta, GA, March 26-30, 2006