20333-68-0Relevant articles and documents
Concerted mechanisms of the reactions of phenyl and 4-nitrophenyl chlorothionoformates with substituted phenoxide ions
Castromaria Cubillos, Enrique A.,Santos, José G.
, p. 6820 - 6823 (1998)
The title reactions are subjected to a kinetic study in 3% (v/v) dioxane in water, 25.0 °C, ionic strength 0.2 M (KC1). By following the reactions spectrophotometrically, pseudo-first-order rate coefficients (￡0bsd) are found under an excess of the nucleophile. Plots of ￡0bsd vs phenoxide anion concentration at constant pH are linear, with the slope (￡N) independent of pH. The Bro?nstedtype plots (log AN vs pKa of the phenols) are linear with slopes β= 0.55 and 0.47 for the reactions of the phenyl and the 4-nitrophenyl derivatives, respectively. These Bro?nsted slopes are in agreement with the ones found in the concerted reactions of the same nucleophiles with reactive phenyl esters and acetic anhydride in water. In contrast to the concerted mechanism of the title reactions that of the same substrates with secondary alicyclic amines is stepwise, which means that substitution of an amino moiety in a tetrahedral intermediate with a phenoxy group by another phenoxy group destabilizes the intermediate to the point that it no longer exists.
Alkaline hydrolysis of Y-substituted phenyl phenyl thionocarbonates: Effect of changing electrophilic center from C=O to C=S on reactivity and mechanism
Kim, Song-I,Park, Hey-Ran,Um, Ik-Hwan
body text, p. 179 - 182 (2011/10/31)
Second-order rate constants (kOH-) have been measured spectrophotometrically for reactions of Y-substituted phenyl phenyl thionocarbonates (4a-i) with OH- in 80 mol % H2O/20 mol % DMSO at 25.0 ± 0.1 °C. The ksu
Radical 1,2-o→c transposition for conversion of phenols into benzoates by o-neophyl rearrangement/fragmentation cascade
Baroudi, Abdulkader,Alicea, Jeremiah,Alabugin, Igor Y.
supporting information; experimental part, p. 7683 - 7687 (2010/08/22)
Figure Presented Radical merry-go-round! Diaryl thiocarbonates, available in a single step from phenols, can be directly transformed into benzoates by a new radical cascade that transposes O and C atoms at the aromatic core. The cascade bypasses the common Barton McCombie fragmentation in favor of the usually unfavorable O-neophyl rearrangement, which is rendered irreversible and efficient by a highly exothermic C-S bond scission in the O-centered radical (see scheme; FG = functional group).
