0000000000285764
AUTHOR
Bin Su
Ionic partition diagram of tetraphenylporphyrin at the water|1,2-dichloroethane interface
diagram of 5,10,15,20-tetraphenyl-21H,23H-porphine (H2TPP) at the water|1,2-dichloroethane interface using a simple Born solvation model. This zone diagram shows under which form this porphyrin is present, i.e. neutral, monoprotonated or diprotonated, and in which phase i.e. either in the aqueous or the organic phase as a function of the aqueous pH and the interface polarisation that can be controlled externally or by the distribution of supporting electrolytes. This diagram explains why the monoprotonated form has been difficult to observe when doing biphasic pH titrations
Dioxygen reduction by cobalt(II) octaethylporphyrin at liquid|liquid interfaces.
Oxygen reduction catalyzed by cobalt(II) (2,3,7,8,12,13,17,18-octaethylporphyrin) [Co(OEP)] at soft interfaces is studied by voltammetry and biphasic reactions. When Co(OEP) is present in a solution of 1,2-dichloroethane in contact with an aqueous acidic solution, oxygen is reduced if the interface is positively polarized (water phase versus organic phase). This reduction reaction is facilitated when an additional electron donor, here ferrocene, is present in excess in the organic phase.
Evidence of tetraphenylporphyrin monoacids by ion-transfer voltammetry at polarized liquid|liquid interfaces
We present a simple methodology to illustrate the existence of tetraphenylporphyrin monoacid based on ion-transfer voltammetry at a polarized water|1,2-dichloroethane interface and organic pK values are also estimated.
Proton pump for O2 reduction catalyzed by 5,10,15,20-tetraphenylporphyrinatocobalt(II).
The role of 5,10,15,20-tetraphenylporphyrinatocobalt(II) ([Co(tpp)]) as a catalyst on molecular oxygen (O(2)) reduction by ferrocene (Fc) and its two derivatives, 1,1'-dimethylferrocene (DFc) and decamethylferrocene (DMFc) at a polarized water|1,2-dichloroethane (DCE) interface has been studied. The water|DCE interface essentially acts as a proton pump controlled by the Galvani potential difference across the interface, driving the proton transfer from water to DCE. [Co(tpp)] catalyzed O(2) reduction by Fc, DFc and DMFc is then followed to produce hydrogen peroxide (H(2)O(2)). The catalytic mechanism is similar to that proposed by Fukuzumi et al. for bulk reactions. This interfacial system …