38878-40-9

Upstream product

• 123-30-8 4-amino-phenol 
• 299-36-5 ascorbic acid anion 
• 62-53-3 aniline 
• 769-92-6 4-tert-Butylaniline 
• 104-94-9 4-methoxy-aniline 
• 106-49-0 p-toluidine 

Downstream Products

• 60-87-7 10-[2-(dimethylamino)propyl]phenothiazine 
• 769-92-6 4-tert-Butylaniline 
• 106-49-0 p-toluidine 
• 123-30-8 4-amino-phenol 
• 104-94-9 4-methoxy-aniline 
• 62-53-3 aniline 

Relevant academic research and scientific papers

Redox and acidity properties of 4-substituted aniline radical cations in water

By means of pulse radiolysis the one-electron reduction potentials of twelve 4-substituted aniline radical cations and the pKa values of eight 4-substituted aniline radical cations have been determined. Both the potentials and the pKa values were shown to be linearly dependent on the Brown σp+ values for the 4-substituents. The one-electron reduction potentials were also compared to previously reported electrochemically determined E1/2 values resulting in good agreement between the two sets of data. By combining the one-electron reduction potentials and the pKa values the N-H bond dissociation energies of some 4-substituted anilines were calculated, also showing a linear substituent dependence. The absolute N-H bond dissociation energy of aniline found was close to a previously reported value.

Phenothiazine Radical-cations : Electron Transfer Equilibria with Iodide Ions and the Determination of One-electron Redox Potentials by Pulse Radiolysis

The establishment of an equilibrium reaction between iodine radical-anions, I2-., the protonated form of the phenothiazine, promethazine, PZH+, its related radical-cation, PZH2+., and iodine ions, I-, has been observed directly by pulse radiolysis .From measurements of the radical-anion and radical-cation I2-. + PZH+ PZH2+. + 2I- (i) equilibrium concentrations at different iodide and promethazine concentrations a value for the equilibrium constant K3 = 94 mol dm-3 has been attained.A closely similar value K3 = 85 mol dm-3 has been derived from a kinetic analysis of the radical concentrations as equilibrium was approached.Taking the mean value K3 = 90 +/- 5 mol dm-3 and a reported value of K8 = 8.85 x 10-6 mol dm-3 for the equilibrium reaction (ii) the difference in redox potentials given by equation (iii) can be calculated.Values of I2-. I. + I- (ii) ΔEo = Eo(PZH2+./PZH+) - Eo(I./I-) = -0.415 V (iii) Eo(PZH2+./PZH+) = +0.865 V and Eo(I./I-) = +1.31 V have been reported previously.Our experimental result agrees very well with the calculated ΔEo = -0.445 V based on these independently derived redox potentials.Measurements of absolute rate constants for the reaction of PZH2+. and related radical-cations from chlorpromazine (3) and metiazinic acid (2) with ascorbate (4) (AH-) and α-tocopherol (5) (α-T) indicate that such electron transfer equilibria are likely to exist also with other phenothiazine cations and strongly reducing compounds.The following bimolecular rate constants have been obtained: k(PZH2+. + AH-) = 8.2 x 108, k(PZH2+. + α-T) = 1.1 x 108, k(MZ+/-. + AH-) = 9.0 x 107, and k(MZ+/-. + α-T) = 1.3 x 108 mol-1 dm3 s-1.