Alkanes nitro-, reaction with

Mechanism The reaction of and A -steroids with nitrosyl fluoride to form ni trimines is best discussed in conjunction with the nitrosyl chloride reaction leading tothe5a-chloro-6 -nitro steroids (33). Since nitroso alkanes are oxidized with nitrosyl chloride to nitro alkanes it is believed that 5a-chloro-6j5-nitro steroids are formed in this way from an initially formed 5a-chloro-6 -nitroso adduct. The same is true for nitrosyl fluoride up to the stage of the nitroso fluoride (56). Since NOF is a weaker oxidizing agent than NOCl the nitroso fluoride tautomerizes to the fluoro oxime (57) at a rate... 

Gem-nitro imidazolyl alkanes undergo Sjy l reactions with the anion of various nitroalkanes, as shown in Eq. 5.36.54 The nitro group is replaced by hydrogen in 80-90% yield on treatment with Bu3SnH (see Chapter 7, which discusses radical denitration). 

A few nitro compounds have been obtained in good yields by the interaction of reactive halogen compounds with aci-nitro alkanes. The reaction is usually complicated in that both C- and 0-alkylation occurs. If the stability of the aci form of the nitro compound is high, then the tendency is toward alkylation on carbon rather than on oxygen. An example is the condensation of p-nitrobenzyl chloride with the sodium salt of nitro-ethane to give an 83% yield of 1-p-nitrobenzylnitroethane, P-OjNC.H CHjCHCNOjXIHj. ... 

Gasoline hydrocarbons volatilized to the atmosphere quickly undergo photochemical oxidation. The hydrocarbons are oxidized by reaction with molecular oxygen (which attacks the ring structure of aromatics), ozone (which reacts rapidly with alkenes but slowly with aromatics), and hydroxyl and nitrate radicals (which initiate side-chain oxidation reactions) (Stephens 1973). Alkanes, isoalkanes, and cycloalkanes have half-lives on the order of 1-10 days, whereas alkenes, cycloalkenes, and substituted benzenes have half- lives of less than 1 day (EPA 1979a). Photochemical oxidation products include aldehydes, hydroxy compounds, nitro compounds, and peroxyacyl nitrates (Cupitt 1980 EPA 1979a Stephens 1973). 

Rann et al. reported the dramatic influence of a new tailor-made, task-specific, and stable ionic liquid, butyl methyl imidazolium hydroxide ([bmim][OH]), in Michael addition. They have discovered that a task-specific ionic liqnid [bmim][OH] efficiently promoted the Michael addition of 1,3-dicarbonyl compounds, cyano esters, and nitro alkanes to a variety of conjugated ketones, carboxylic esters, and nitriles withont reqniring any other catalyst and solvent (Fig. 12.21) [16]. Very interestingly, all open-chain 1,3-dicarbonyl componnds such as acetylacetone, ethyl ace-toacetate, diethyl malonate, and ethyl cyanoacetate reacted with methyl vinyl ketone and chalcone to give the usual monoaddition products, whereas the same reactions with methyl acrylate or acrylonitrile provided exclusively bis-addition products. 

NITROALDOL REACTIONS WITH SILYL NITRONATES AND WITH a,a DOUBLY DEPROTONATED NITRO ALKANES... 

Mc.Murrey and co-workers modified the reaction by carrying it out in a reductive medium of TiCla followed by hydrolysis and an oxidizing medium of O3 (92a] and (92b] respectively. Sec also Bartlett et al. (93 ]. They used r-butyl hydroperoxide in the presence of peniavalent vanadium salt as a catalyst, Korn-blum and Wade (94a] gave an unusual method of oxidation of secondary nitro-alkanes to ketones with nitrous esters and sodium nitrite at room temperature ... 

Nitro[ G]alkanes have been obtained from labeled methyl-, ethyl-, and propyl iodide by reaction with silver nitrite by the online process presented in Fig. 41.10 (Schoeps et al. 1989 Schoeps and Halldin 1992). 

At high temperature (above about 400°C) alkanes undergo nitration with nitric acid (HONO2). The reaction has all of the characteristics of the radical processes already discussed and, except for methane (CH,) (Equation 6.10), the large number of products produced from most alkanes due to carbon-carbon bond cleavage and introduction of more than one nitro group (-NO2) Unaits the utility of the process. 

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