Journal of the Chemical Society - Faraday Transactions p. 1203 - 1210 (1993)
Update date:2022-08-28
Topics:
Thompson, Katherine M.
Griffith, William P.
Spiro, Michael
The kinetics of the oxidation of phenolphthalein by alkaline hydrogen peroxide have been studied in aqueous solution over a range of pH, ionic strength and temperature.The rate of reaction was found to be first order in both phenolphthalein and hydrogen peroxide.Use of free radical and singlet oxygen trapping agents have ruled out the involvement of these species in the reaction.The variation of the rate constant with pH and ionic strength has shown that at pH >11 the main reaction is that between the pink bisphenolate form of phenolphthalein and the perhydroxyl anion, HO2(1-).At pH 9, epoxidation by the hydrogen peroxide molecule contributed most of the overall rate constant.Borate-buffered solutions gave a faster rate of reaction than those in hydrogencarbonate or ammonia buffers.Experiments over the temperature range 21.0-45.0 deg C lead to activation energies of 43.3 and 48.4 kJ mol-1 and entropies of activation of -149 and -131 J K-1 mol-1 at 298 K, in carbonate and borate buffers, respectively.A mechanism for the reaction is proposed.
View Morewebsite:http://www.enbridgepharm.com
Contact:+86-510-83591909
Address:Huishan Zone, Wuxi City, Jiangsu Province, P.R.China
Laohekou Jinghong Chemical Co.,Ltd
Contact:+86-0710-3702747
Address:163.East，Huagong Road，Laohekou
Anhui Jiatiansen Agrochemical Co.,Ltd
Contact:15366811918
Address:chemical industrial park,xiangyu town,dongzhi county,anhui,china
Nanjing distinctions Medical Technology Co., Ltd.(expird)
Contact:+86-15996203785 13914714059
Address:nanjing,jiangsu , China
Contact:86-571-87758773
Address:Room604 ,6F, Block A1-3 Xixi Plaza,No. 588 Wenyi West RD, Hangzhou,310012, China
Doi:10.1002/jhet.3155
(2018)Doi:10.1039/c39840000257
(1984)Doi:10.1080/0049825021000017948
(2003)Doi:10.1016/j.phytol.2013.06.004
(2013)Doi:10.1021/acs.joc.8b03015
(2019)Doi:10.1039/c0ob00337a
(2010)
