Tetraphenylporphyrin cobalt derivatives

In addition, E /2 for the M(II/I) couple of cobalt and nickel macrocycles under CO2 in aprotic media are typically shifted toward cathodic potentials, but remain fully reversible [15]. These results indicate that CO2 binding is fast and reversible for this class of complexes. Similarly, the Fe(0) species formed on reduction of derivatives of Fe fi tetraphenylporphyrins react very rapidly with CO2 [37, 38]. 

A tetraphenylporphyrin derivative with four thiol moieties 9 and a similar bis(cobalt) cofacial diporphyrin with three thiol moieties 10, prepared independently at the same time, electrocatalytically reduce O2 on a variety of gold surfaces [301, 316],... 

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