The reaction of ethyl linoleate (1) with NO2- in different air-equilibrated acidic media resulted in the formation of complex patterns of products, some of which could be isolated by repeated TLC fractionation and were formulated as the nitroalkenes 2-5, the novel (1E, 5Z)-3-nitro-1,5-hexadienes 6/7, the novel (E,E)-1,5-dinitro-1,3-pentadiene derivatives 8 and 9, and the nitro alcohols 10/11 and 12/13 by extensive GC-MS and 2D NMR analysis, as aided by 1D Hartmann-Hahn proton mapping experiments. Similar reaction of methyl oleate gave mainly nitroalkene (14/15) and allylic nitro derivatives (16/17). Formation of 2-13 may be envisaged in terms of HNO2-mediated nitration pathways in which regioisomeric beta-nitroalkyl radical intermediates derived from attack of NO2 to the 1,4-pentadiene moiety of 1 evolve through competitive H-atom abstraction and free radical combination routes
Acid-promoted reactions of ethyl linoleate with nitrite ions. Formation and structural characterization of isomeric nitroalkene, nitrohydroxy and novel 3-nitro-1,5-hexadiene and 1,5-dinitro-1,3-pentadiene products / Napolitano, Alessandra; Camera, Emanuela; Picardo, Mauro; D'Ischia, Marco. - In: JOURNAL OF ORGANIC CHEMISTRY. - ISSN 0022-3263. - STAMPA. - 65:(2000), pp. 4853-4860. [10.1021/jo000090q]
Acid-promoted reactions of ethyl linoleate with nitrite ions. Formation and structural characterization of isomeric nitroalkene, nitrohydroxy and novel 3-nitro-1,5-hexadiene and 1,5-dinitro-1,3-pentadiene products.
NAPOLITANO, ALESSANDRA;D'ISCHIA, MARCO
2000
Abstract
The reaction of ethyl linoleate (1) with NO2- in different air-equilibrated acidic media resulted in the formation of complex patterns of products, some of which could be isolated by repeated TLC fractionation and were formulated as the nitroalkenes 2-5, the novel (1E, 5Z)-3-nitro-1,5-hexadienes 6/7, the novel (E,E)-1,5-dinitro-1,3-pentadiene derivatives 8 and 9, and the nitro alcohols 10/11 and 12/13 by extensive GC-MS and 2D NMR analysis, as aided by 1D Hartmann-Hahn proton mapping experiments. Similar reaction of methyl oleate gave mainly nitroalkene (14/15) and allylic nitro derivatives (16/17). Formation of 2-13 may be envisaged in terms of HNO2-mediated nitration pathways in which regioisomeric beta-nitroalkyl radical intermediates derived from attack of NO2 to the 1,4-pentadiene moiety of 1 evolve through competitive H-atom abstraction and free radical combination routesI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.