A porphyrazine macrocycle with eight peripheral cyano groups has been made for the first time by researchers in Russia. 

The highly functionalised octacyanoporphyrazine molecule has been synthesised using a metal templating method and tetracyanoethylene (TCNE) units as building blocks. Larisa Klapshina at the Russian Academy of Sciences and colleagues from France and Belarus have made the highly electron deficient tetrapyrrole compound in the form of two complexes either with vanadyl or ytterbium ions. 

The complexes, in their solid state, are stable complexes and soluble in polar solvents.

The vanadyl octacynanoporphyrazine is made using a bis(arene)vanadium compound as a starting material and by the coordination with four TCNE units. The same synthetic approach was used to make the ytterbium complex.

'The octacyanoporphyrazine framework, when incorporated into a polymeric matrix shows interesting optical properties,' said Klapshina, 'making the material promising for applications in electroluminescent and photovoltaic devices.' 

Also, the complexes may be important in biochemical applications as a photosensitizer for photodynamic antitumour therapy and for medical diagnostics.  

Alison Stoddart