Synfacts 2011(12): 1301-1301  
DOI: 10.1055/s-0031-1289390
Synthesis of Materials and Unnatural Products
© Georg Thieme Verlag Stuttgart ˙ New York

An All-Organic Porphyrin and its Properties

Contributor(s): Timothy M. Swager, Sébastien Rochat
T. P. Vaid*
University of Alabama, Tuscaloosa, USA
Further Information

Publication History

Publication Date:
18 November 2011 (online)

Significance

Reaction of cobalt porphyrin 1 with diiodoacetylene in the presence of FeCl3 followed by treatment with K2CO3 affords compound 2, which is reduced with SmI2 to form porphyrin 3. Characterization of this neutral C=C porphyrin reveals alternating single and double C-C bonds, owing to the antiaromatic properties of the compound. Further, cyclic voltammetry measurements indicate an easy oxidation of 3 to its dicationic, 18π-electron aromatic form. Chemical oxidation of 3 in the presence of AgOTf affords ionic species 4. NMR measurements and DFT calculations confirm the aromatic character of 4, that does not possess alternating single and double C-C bonds.