Patent GB-604360-A (GB)
Title: Improvements in and relating to the production of organic nitrogen compounds
Filed: 1945-03-12
Abstract: Polymerized nitro-propene is prepared from dinitro-propene or the nitro-propyl nitrates by reacting them with a monohydric alcohol at a temperature of at least 64.6 DEG  C., isolating the resulting nitro-propene by distillation from the reaction mixture in the vapour of the alcohol used, condensing the distillate and treating the condensate with alkali and filtering off the polymerized nitro-propene.  When alcohols containing two or more carbon atoms are used, it is preferred to carry out the reaction in the neighbourhood of the boiling point of the alcohol.  The preferred alcohols are the C1 to C6 aliphatic alcohols and benzyl alcohol.  Super-atmospheric pressure may be employed. The process may be applied to the preparation of nitro olefines or nitro ethers from specified dinitro paraffins with at least three carbon atoms, excluding dinitro-isobutane, and from specified nitro-alkyl nitrates having at least three carbon atoms (see Group IV (b)].ALSO:Nitro-olefines and/or nitro-ethers are prepared from dinitro-paraffins with at least three carbon atoms in which the nitro groups are on adjacent carbon atoms at least one of which has a hydrogen atom attached, but excluding dinitro-isobutane, or from nitro-alkyl nitrates with at least three carbon atoms in which the nitrate and nitro groups are on adjacent carbon atoms and that carbon atom to which the nitro group is attached has also a hydrogen atom attached, by reacting them with a monohydric alcohol at a temperature of at least 64.6 DEG  C.  With alcohols containing two or more carbon atoms higher temperatures are preferred, for example, those in the neighbourhood of the boiling point of the alcohol used; superatmospheric pressure may be employed. Dinitro-propane and nitro-propyl nitrates yield nitro-propene which is isolated by distillation from the reaction mixture in the vapour of the alcohol used, the distillate being condensed and then fractionally distilled under reduced pressure, or treated to yield polymerized nitropropylene (see Group IV (a)).  The nitropropene readily reacts with more of the alcohol to form nitro-alkyl ethers; to obtain the nitropropyl ether as main product, prolonged heating under reflux is required.  The preferred alcohols are the aliphatic alcohols having 1 to 6 carbon atoms and benzyl alcohol.  Nitrites and nitrates of the alcohols are formed in these reactions and may be recovered by fractional distillation.  The starting materials may be prepared by the methods described in Specifications 580,260 and 587,992.  In examples: (1) methyl alcohol and 1-2-dinitro propane are refluxed for 17 hours yielding 1 - nitro - 2 - methoxy - propane, methyl nitrite being distilled off as formed; (2) ethanol and 1-nitro propanol-2 nitrate are refluxed for 7 hours yielding 1-nitro 2-ethoxy propane; (3) methyl alcohol and 2,4,4-trimethyl-1,2-dinitro pentane are refluxed for 5 days yielding 2,4,4-trimethyl pentene-1; (4) methyl alcohol and nitrotertiary butylnitrate are refluxed for two days yielding a -nitroisobutene.  1-Nitro 2-methoxy propane, 1-nitro 2-ethoxy propane and 2,4,4-trimethyl pentene-1 are believed to be new.  The Provisional Specification describes also the treatment of dinitro alicyclic hydrocarbons and nitro alicyclic nitrates, the nitro and nitrate groups being on adjacent carbon atoms as characterized above, and is not limited as regards reaction temperature, the use of room temperatures being mentioned.