gemini-Porphyrazines:  The Synthesis and Characterization of Metal-Capped cis- and trans-Porphyrazine Tetrathiolates Academic Article uri icon


  • Peripherally-functionalized porphyrazines of the form M[pz(A(n):B(4-n))] (inset 1), where A and B symbolize functional moieties (e.g., a-d in Table 1) fused directly to the β-positions of the pyrroles, have the potential to serve in a wide range of applications. Previously, we reported the synthesis of porphyrazine di- and octathiolate ligands, M[pz(b3:c1)] and M[pz(c4)], respectively, where b is a fused benzo ring and c represents two thiolates fused at the β-pyrrole positions to form a dithiolene capable of the peripheral chelation of a metal ion. We describe here a general strategy that solves the more difficult problem of preparing and isolating the porphyrazinetetra- and hexathioethers and the porphyrazinetetra- and hexathiolates, with the focus being the trinuclear metal complexes of the trans- and cis-porphyrazinetetrathiolate isomers (trans- and cis-M[pz(b2:d2)]), denoted as gemini porphyrazines. Spectroscopic and electrochemical studies reveal that the physical properties of the cis- and trans-tetrathioether porphyrazines exhibit intriguing differences associated with their distinct molecular symmetries. These functionalized macrocycles have been used to prepare the trans- and cis-gemini porphyrazines 14 and 16, the two isomeric porphyrazinetetrathiolate macrocycles that are peripherally-metalated with two bis(triethylphosphine)platinum(II) moieties. The X-ray structure of the trans isomer, 14, is presented; it is the first structure of a porphyrazine or phthalocyanine having a trans-type substitution pattern.

published proceedings

  • Journal of the American Chemical Society

author list (cited authors)

  • Sibert, J. W., Baumann, T. F., Williams, D. J., White, A., Barrett, A., & Hoffman, B. M

citation count

  • 62

complete list of authors

  • Sibert, John W||Baumann, Theodore F||Williams, David J||White, Andrew JP||Barrett, AGM||Hoffman, Brian M

publication date

  • January 1996