Nitro compounds from alkanes

The radical chain reduction of thioformates, which are generated from tertiary alcohols, with tri-n-butyltin hydride has been reported by Barton and co-workers, and the mildness of tri-n-butyltin hydride as a reducing agent has been nicely demonstrated by the conversion of the bromo-endoperoxide (1) into the endoperoxide (2). The known reduction of nitro-compounds to alkanes. 

In the course of gas-phase nitration of alkanes with NO, increase in the yield of nitroalkane can be attained by increase in the rate of radical formation and retardation of oxidative reactions in which the free radicals take part. It is probable that the catalytic effect of molecnlar iodine on the nitration of propane with NO is associated mainly with the tendency of inactive iodine atoms to retard the oxidation of hydrocarbons [11]. In the presence of 0.15% I, the CO content of the reaction products is reduced from 22.1 % to 5.2%. Simultaneously, the yield of nitro compounds is increased by 10%. 

The reactions of halide and azide ions (see above), cyanide ion (see Chap. 7) and thiocyanate ions (see Sect. 13.7) have all been discussed. In the general context of halides and pseudohalides, it should be noted that nitrite ion has been successfully phase-transferred [31, 32]. The yields for the formation of nitroalkanes in either crown [31 ] or quaternary ion catalyzed [32] processes are fair to good for primary alkanes and poor for secondary systems. Bromocyclohexane, for example, afforded only traces of nitrocyclohexane when treated with nitrite ion, the by-products resulting presumably from oxygen attack (nitrite ester formation) or elimination. The conversion of n-octy bromide into the corresponding nitro-compound is formulated in equation 9.14 and several examples of the transformation are recorded in Table 9.6. 

The usual order or elution of organic solutes is dependent on the type of polar functional groups, number of groups, and orientation. A listing of functional groups from low k (capacity factor which is proportional to retention) to high k follows Alkane < olefins < aromatic organic halides < sulfides < ethers < nitro compounds... 

The easy addition at C-5 of 1,2,4-triazines is shown by the VNS (3.3.3) reaction of the 3-methylthio derivatives in the absence of activating groups a closely related addition of nitro-alkanes represents a very useful nucleophilic acylation. The ready displacement of methylthio from the same compound is also significant. ... 

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