Journal of the Chemical Society - Faraday Transactions p. 2927 - 2936 (1990)
Update date:2022-08-11
Topics:
Lightfoot, Phillip D.
Roussel, Pascal
Veyret, Bernard
Lesclaux, Robert
The self-reaction of neopentylperoxy radicals, neo-C5H11O2 (NPTO2): NPTO2 + NPTO2 --> 2 t-C4H9VH2O + O2 (1a) --> t-C4H9CHO + t-C4H9CH2OH + O2 (1b) --> t-C4H9CH2OOCH2C4H9-t + O2 (1c) has been studied from 248 to 373 K and from 50 to 760 Torr total pressure.The neopentylperoxy radicals formed via channel (1a) react, under most experimental conditions, by unimolecular decomposition: t-C4H9CH2O + M --> t-C4H9 + HCHO + M. (2) The t-butyl radicals so formed are rapidly converted into t-butylperoxy radicals under the conditions employed in this work; these radicals are unreactive on the timescale of the NPTO2 decay and enable the branching ratio for reaction (1) to be determined via their UV absorption.The overall rate constant for reaction (1) diaplays a strong negative temperature dependence, being well described by k1/cm3 molecule-1 s-1 = 3.02 x 10-19(T/298)9.46 exp(4260/T) over the temperature range studied here.The non-terminating channel (1a) becomes increasingly important with increasing temperature, with β = (197+/-67)exp<-(1658+/-98)/T>, where β is the ratio of those radicals which react via the non-terminating channel (1a) to those which react via the terminating channels (1b) and (1c).By measuring the reduction in the fraction of NPTO2 radicals converted to t-butylperoxy radicals with increasing oxygen concentration, rate constants for reaction (2) were determined relative to that of CH3O2; both are similar in shape and magnitude to those of other alkylperoxy radicals, displaying maxima around 240 nm, with ?240nm (NPTO2) / cm2 molecule-1 = (6.2 +/- 1.1) x 10-18 and ?240nm (t-C4H9O2) / cm2 molecule-1 = (4.7 +/- 0.8) x 10-18.The self-reaction of t-butylperoxy radicals: 2 t-C4H9O2 --> 2 t-C4H9O + O2 (3) was also briefly studied, resulting in k3/cm3 molecule-1 s-1 ca. 1.0 x 10-11 exp(-3894/T).Errors are 1?.
View MoreJIANGXI AIFEIMU TECHNOLOGY CO.,LTD
Contact:+86-570-6040289
Address:FINECHEMICAL PARK,ZIBU TOWN,WANNIAN COUNTY,JIANGXI PROV.,CHINA,ZIP
shanghai hekang chemical co.ltd
Contact:021-54173790
Address:328 WuHe Road, Building #A, 2nd Floor, Minhang, Shanghai 201109, China
shanghai hekang chemical co.ltd
Contact:021-54173790
Address:328 WuHe Road, Building #A, 2nd Floor, Minhang, Shanghai 201109, China
Zhejiang Kangfeng Chemical Co.,LTD.
Contact:+86-579-86709687
Address:Xueshizhai Industrial Zone, Weishan Town,Dongyang City, Zhejiang Province ,China
Shaanxi Lighte Optoelectronics Material Co., Ltd.
Contact:+86-29-88320728-622/619/620
Address:No.55 INDUSTRY ROAD 2,XI'AN NATIONAL CIVIL AEROSPACE INDUSTRIAL PARK.XI'AN China 710065.
Doi:10.1021/ja4010305
(2013)Doi:10.1016/j.bmcl.2007.10.003
(2007)Doi:10.1016/j.tet.2020.131222
(2020)Doi:10.1002/ejoc.201901547
(2019)Doi:10.1039/c6ob01731b
(2016)Doi:10.1002/cbic.201700555
(2018)