84559-79-5Relevant articles and documents
Photoreaction mechanisms of 2-bromophenols studied by low-temperature matrix-isolation infrared spectroscopy and density-functional-theory calculation
Akai, Nobuyuki,Kudoh, Satoshi,Takayanagi, Masao,Nakata, Munetaka
, p. 591 - 597 (2002)
Photoreaction mechanisms of 2-bromo, 2-bromo-4-chloro and 2,4-dibromophenols in low-temperature argon matrices have been investigated by Fourier transform infrared spectroscopy. Density-functional-theory calculations are performed to assign the observed i
Observation of Transient Cyclohexadienones during the Aqueous Bromination of Phenols
Tee, Oswald S.,Iyengar, N. Rani
, p. 455 - 459 (2007/10/02)
Transient 4-bromo-2,5-cyclohexadienone intermediates have been observed during the aqueous bromination of phenol and several methylated derivatives.They enolize to the corresponding p-bromophenols by both acid-catalyzed and water-catalyzed pathways in the pH range 0-6.Studies carried out in buffers also indicate both general acid catalysis (α ca 0.0) and general base catalysis (β=0.54).The latter is ascribed to simple rate-limiting proton abstraction, but the former is not so easily rationalized.The very low α is attributed to a termolecular transition state (water, substrate, and general acid) in which the dienone becomes more anion-like than cation like.This seemingly anomalous behaviour can be explained by the very large enol/keto ratio (ca. 1011) for phenol.
