Kinetics of formation, dissociation, and redox reactions of the benzyl radical-Cu(II) ion complex in a 10% acetonitrile-90% water mixture
✍ Scribed by Ahmed Mayouf; Helge Lemmetyinen; Irina Sychttchikova; Jouko Koskikallio
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 350 KB
- Volume
- 24
- Category
- Article
- ISSN
- 0538-8066
No coin nor oath required. For personal study only.
✦ Synopsis
The rate constant of formation, dissociation, and redox reaction of the benzyl radicalcopper(I1) ion complex have been determined at temperatures from 274 K to 333 K by laser flash photolysis of 1,3-diphenyl-2-propanone (DBK) in a 10% acetonitrile-90% water mixture containing copper(I1)perchlorate. Rate constants were calculated from time resolved absorbances of both benzyl radicals (Bz) at 315 nm and benzyl-copper complexes (BzCu") at 375 nm. Values of the rate constants of the formation of BzCu" complex were fitted to the equation
and the rate constant of the reverse reaction of BzCU" complex to the equation log k4/s-' = (7.58 2 0.05) -[(7.0 t 0.7) k J mol-'/2.
303 R T ]
The rate constant of the redox reaction of BzCu" complex to benzyl alcohol and copper(1) ion can be described by the equation log ks/s-' = (6.61 t 0.1) -[(6.0 2 0.5) k J mol-'/2.
303 R T ]
The first order rate constant of dissociation of phenylacetyl radical formed initially in the flash photolysis of DBK is given by the equation log kz/s-' = (9.58 t 0.04) -[(19.5 t 0.8) k J mol-'/2.303 R T ]