M. Abe, Youngjae You, M. Detty
Sep 19, 2002
Citations
0
Influential Citations
32
Citations
Journal
Organometallics
Abstract
meso-Tetraphenyl-21-telluraporphyrins 3 and 4 act as catalysts for bromination reactions with H2O2 and NaBr. Oxidation of telluraporphyrin 3 with excess H2O2 follows pseudo-first-order kinetics with a second-order rate constant of 0.85 ± 0.02 M-1 s-1 at 20.5 °C in 1:1 CH2Cl2/ethanol. Bromination of 4-pentenoic acid in two-phase mixtures of CH2Cl2 and pH 6 phosphate buffer with a stoichiometric amount of NaBr in the presence of a 50% excess of H2O2 follows second-order kinetics as monitored by the loss of 4-pentenoic acid. Reactions of 4-pentenoic acid and 1,3,5-trimethoxybenzene with excess H2O2 and excess NaBr follow pseudo-first-order kinetics and are pseudo-first-order in bromide in two-phase mixtures. Brominations of 4-pentenoic acid were conducted with initial concentrations of 0.2 M 4-pentenoic acid, 1.5 M H2O2, and 1.0 M in NaBr in a two-phase system of CH2Cl2 and pH 6 phosphate buffer. Brominations of 1,3,5-trimethoxybenzene were conducted with initial concentrations of 0.2 M 1,3,5-trimethoxybenze...