Dinitrogen tetroxide alkenes

The addition of dinitrogen tetroxide across the double bonds of electron deficient fluorinated alkenes is a particularly useful route to v/c-dinitro compounds where yields are frequently high 8,37 tetrafluoroethylene gives a 53 % yield of l,2-dinitro-l,l,2,2-tetrafluoroethane. ... 

Finally, an interesting deamination reaction of aziridines was reported, in which treatment of N-unsubstimted aziridines (152) with dinitrogen tetroxide (2 equiv) in the presence of Et3N results in clean deamination to provide the corresponding alkenes (154) with remarkably high yields (>90%). The reaction is believed to proceed via the N-nitroso intermediate 153, so that the driving force for the reaction is liberation of N O <99SC1241>. 

Several nitrogen oxides dinitrogen trioxide, dinitrogen tetroxide and dinitrogen pentoxide can readily add to alkenes the resultant nitronitroso- dinitro- and... 

The reaction of dinitrogen tetroxide with alkenes generally gives 1,2-dinitro compounds, fi-ni-tro nitrites and /5-nitro nitrates, often as mixtures, by a radical mechanism (Section 7.2.1.7). However, a /5-nitroso nitrate was obtained by the heterolysis (NO NOf) of dinitrogen tetroxide and ionic addition to 2,3-dimethyl-2-butene71. 

The reaction of alkenes with dinitrogen tetroxide, following a radical mechanism, generally affords mixtures of 1,2-dinitro compounds, /(-nitro nitrites and jS-nitroso nitro compounds. By oxidation of /(-nitro nitrites with dinitrogen tetroxide itself or oxygen, /(-nitro nitrates are produced11 111. 

The type and the stereochemistry of the products depends on the structure of the alkene and the experimental conditions. The use of oxygen as a carrier gas for dinitrogen tetroxide affects the course of the reaction in various ways, depending on the alkene, but it especially prevents reduction of dinitrogen tetroxide to dinitrogen trioxide and thereby permits a cleaner product mixture to be obtained, or it can divert the reaction course toward the formation of /(-nitro nitrates115. 

Similarly, from 1,2-dimethylcyclohexene the fraa.v-dinitro derivative 4 was prepared (together with several minor byproducts) with more than 30 1 stereoselectivity118 the trans stereochemistry was demonstrated by the separation of the enantiomers on a chiral capillary GC column. Slow addition of the alkene to an excess of dinitrogen tetroxide is crucial to the success of the dinitration. The trans-diamine 5 was obtained by catalytic hydrogenation. 

Fluoronitroso compounds can be prepared by the simultaneous addition of F and NO to alkene double bonds by the use of either nitrosyl fluoride317-319, 22, 29,342-344 or a mixture of dinitrogen tetroxide and potassium fluoride.320 The nitrosofluorination reactions of hexa-fluoropropene, perfluoro(2-methylpropcne) and perfluorocyclobutene by these two different methods are summarized in Table 27. Additionally, the reactions of nitrosyl fluoride with chloro-trifluoroethene,319 with alkyl perfluorovinyl ethers.317 and with pcrfluoro(2-methylacryloyl fluoride)344 are listed. 

Nitroacetamidation of conjugated dienes is efficient when a solution of nitronium tetrafluoroborate in acetonitrile obtained by anodic oxidation of dinitrogen tetroxide is used substantial amounts of both 1,2- and 1,4-adducts are usually obtained.34 Some conjugated nitroalkenes can be readily prepared by reaction of alkenes with sodium nitrite and iodine under mild conditions (Scheme 158).347... 

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