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Organic Chemistry

Method of Preparation of Nitro alkanes

Method of preparation of Nitro alkanes

  • From Alkyl Halide:

Haloalkanes upon reaction with silver nitrite, nucleophilic substitution takes place to yield nitroalkanes. Aromatic nitro compounds cannot be prepared by this method because haloarenes undergo electrophilic substitution. The reactivity of haloalkanes is

R-I> R-Br> R-Cl> R-F

Nitroalkanes can be prepared from the alkyl halide by heating with an alcoholic solution of silver nitride.

  • From α-halogenated acids

Nitroalkanes are also obtained by the acids that consists of α – hydrogen. The acid is treated with the sodium nitrite is gently heated to obtain alkyl nitrate and carbon dioxide. The reaction proceeds as:

  • From Hydrocarbon( Nitration of alkanes)

Nitration of alkanes is usually carried out with fuming nitric acid ( HNO3 + NO2) at a temperature between 423- 673 K. The ease of nitration is:

This method has got some limitation as long chain alkanes undergo fragmentation at higher temperature.