Helvetica Chimica Acta p. 2399 - 2424 (2006)
Update date:2022-08-11
Topics:
Kirsch, Michael
Korth, Hans-Gert
Wensing, Angela
Lehnig, Manfred
Sustmann, Reiner
De Groot, Herbert
The reaction of peroxynitrite/peroxynitrous acid with morpholine as a model compound for secondary amines is reinvestigated in the absence and presence of carbon dioxide. The concentration- and pH-dependent formation of N-nitrosomorpholine and N-nitromorpholine as reported in three previous papers ([25] [26] [14]) is basically confirmed. However, 13C-NMR spectroscopic product analysis shows that, in the absence of CO2, N-hydroxymorpholine is, at pH≥7, the major product of this reaction, even under anaerobic conditions. The formation of N-hydroxymorpholine has been overlooked in the three cited papers. Additional (ring-opened) oxidation products of morpholine are also detected. The data account for radical pathways for the formation of these products via intermediate morpholine-derived aminyl and α-aminoalkyl radicals. This is further supported by EPR-spectrometric detection of morpholine-derived nitroxide radicals, i.e., morpholin-4-yloxy radicals. N-Nitrosomorpholine, however, is very likely formed by electrophilic attack of peroxynitrite-derived N2O4. 15N-CIDNP Experiments establish that, in the presence of CO2, N-nitro- and C-nitromorpholine are generated by radical recombination. The present results are in full accord with a fractional (28±2% ) homolytic decay of peroxynitrite/peroxynitrous acid with release of free hydroxyl and nitrogen dioxide radicals.
View MoreContact:+86-15850770348
Address:51 OF XIANGFANGCUN ROAD, Nanjing 210002, China
Jingzhou TianHe Sci&Tech Chemical Co., Ltd.
Contact:86-716-8331612
Address:Jiangjin Road, #18, High-grade technology industries development district, Jingzhou city, Hubei province
Shijiazhuang Frontierchem Co., Ltd.
Contact:+86-311-89271196
Address:4-4-202 No.15 Biandian Street,Shijiazhuang
Weihao Chemtech (ChangZhou) Co., Ltd.
Contact:051989185693
Address:NO 217 huangshan Rd ,Changzhou
Jiangxi Hito Chemical Co., Ltd.
Contact:+86-792-3170318
Address:No. 6, Tianhong Ave., Xinghuo Industry Park, Yongxiu, Jiujiang, Jiangxi, China
Doi:10.1016/S0040-4039(00)87156-7
(1982)Doi:10.1016/S0025-5408(01)00819-4
(2002)Doi:10.1021/acsmedchemlett.0c00043
(2020)Doi:10.1007/s10870-011-0209-1
(2012)Doi:10.1039/c5ra08696e
(2015)Doi:10.1021/j100711a026
(1970)