Fine tuning of the catalytic effect of a metal-free porphyrin on the homogeneous oxygen reduction.
نویسندگان
چکیده
The catalytic effect of tetraphenylporphyrin on the oxygen reduction with ferrocene in 1,2-dichloroethane can be finely tuned by varying the molar ratio of the acid to the catalyst present in the solution. The mechanism involves binding of molecular oxygen to the protonated free porphyrin base, in competition with ion pairing between the protonated base and the acid anion present.
منابع مشابه
Competitive inhibition of a metal-free porphyrin oxygen-reduction catalyst by water.
A stopped-flow method is used to study the effects of water and reactant acid anion TB(-) = tetrakis(pentafluorophenyl)borate on the homogeneous oxygen reduction catalyzed by the protonated tetraphenylporphyrin. Observed competitive inhibition of the catalyst is linked to the DFT free energy of extraction of O(2), water, and TB(-) from the porphyrin complex.
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ورودعنوان ژورنال:
- Chemical communications
دوره 47 19 شماره
صفحات -
تاریخ انتشار 2011