Dinitroethane

2-Dinitroethane may be obtained by the action of nitrogen dioxide on ethylene at low temperature (about 0°C) (Semenoff [73] Demyanov [74], [75]). According to N. Levy, Scaife, Smith [76], the use of a mixture of ethylene with oxygen in the volume ratio of about 4 1 gives good results. 

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The nitroparaffins are named as derivatives of the corresponding hydrocarbons by usiag the prefix "nitro" to designate the NO2 group (1), eg, 1,1-dinitroethane, CH2CH(N02)2- The salts obtained from nitroparaffins and the so-called nitronic acids are identical and may be named as derivatives of either, eg, sodium salt of i7ti-nitromethane, or sodium methanenitronate [25854-38-0]. 

Polynitroparaffkis are stronger acids than the corresponding mononitroparaffins. Thus 1,1-dinitroethane has an ionization constant of 5.6 x 10 in water at 20°C trinitromethane is a typical strong acid with an ionization constant ki the range of 10 to 10 . Neutralization of these substances occurs rapidly, and they may be titrated readily. 

Dinitro-1 -Propanol. CH.3.C(NO a)2-CH2OH crysts mp 88°. Can be prepd by the action of formaldehyde on 1,1-dinitroethane. It is an expl comparable in power to Tetryl and in sensitivity to TNT. It is slightly hygroscopic and fairly stable... 

However, certain facts contradict this interpretation. For example, the silylation of AN with BSA was accelerated after addition of triethylamine, which facilitates AN ionization (185). Besides, the addition of 1,1-dinitroethane leads to an increase in the rate of silylation of methyl nitroacetate with a deficient amount of DPSU. At the same time, the silylation of 1,1-dinitroethane by itself, taken separately with DPSU, occurs faster than silylation of MeC>2CCH2NC>2 (204). Apparently, this is accounted for by the higher nucleophilicity of methyl nitroacetate compared to that of 1,1-dinitroethane. (A separate experiment demonstrated that silyl aci-dinitroethane does not react with methyl nitroacetate.)... 

Approximately at the same time, Shevelev and coworkers studied the reactions of trinitromethane and 1,1-dinitroethane salts with RCOC1 (R=Me or Ph) and detected the corresponding acyl nitronates on the basis of decomposition products and by trapping with various E—X reagents (222) (Scheme 3.64). 

At the same time, two different coupling constants J13 15 were observed in the spectrum of the SiMe3 derivative of 1,1 -dinitroethane, in which the sterically hindered Z isomer is present at very low concentration. By this reason, the process of 1,5-0,0-migration of the SiMe3 group is unobservable on the NMR time scale (272) (Scheme 3.79). 

Both 1,1-dinitroethane (26) and 1,1-dinitropropane, and their methylol derivatives, 2,2-dinitropropanol (25) and 2,2-dinitro-l-butanol respectively, have been synthesized via the Ter Meer reaction. - The formal and acetal of 2,2-dinitropropanol in the form of a 1 1 eutectic is an energetic plasticizer and so the synthesis of 2,2-dinitropropanol has been the subject of much investigation. On a pilot plant scale 2,2-dinitropropanol (25) is synthesized in 60 % overall yield from nitroethane (22). Thus, treatment of 1 -chloronitroethane (23) with potassium nitrite... 

Phenyltrinitromethanes are similarly obtained from the nitration of gem-nitronitronate salts with a solution of dinitrogen tetroxide in ether. 1,1,1-Trinitroethane (73) can be formed in this way from the potassium salt of 1,1-dinitroethane (24). Nitrolic acids, the products formed... 

A range of primary and secondary nitroalkanes and their derivatives have been converted to the corresponding gem-dinitroalkanes via oxidative nitration, including the conversion of nitroethane, 1-nitropropane, 2-nitropropane and 2-nitro-1,3-propanediol to 1,1-dinitroethane (78 %), 1,1-dinitropropane (86 %), 2,2-dinitropropane (93 %) and 2,2-dinitro-1,3-propanediol (77 %) respectively. The silver nitrate used in these reactions can be recovered quantitatively on a laboratory scale and this has led to a study where oxidative nitration has been considered for the large-scale production of 2,2-dinitropropanol (25) from the nitroethane (22). ... 

Oxidative dimerization gives reasonable yields of vtc-dinitroalkanes for some substrates 2,3-dimethyl-2,3-dinitrobutane (48, 53 %) and 3,4-dimethyl-3,4-dinitrohexane (37 %) are obtained from 2-nitropropane (76) and 2-nitrobutane respectively.However, oxidative dimerization fails to convert 1,1-dinitroethane and trinitromethane into 2,2,3,3-tetranitrobutane and hexanitroethane respectively. Additionally, oxidative dimerisation is not a feasible route for the synthesis of v/c-dinitroalkanes from primary nitroalkanes. Although oxidative dimerization is limited in scope, and yields are often poor, the starting materials are usually inexpensive. 

The conjugate 1,4-addition of nitronate anions and other nucleophiles to a-nitroalkenes constitutes an important method for the synthesis of polynitroaliphatic compounds. ° Nitroform (112) reacts with nitroethene (135) and 2-nitropropene to yield 1,1,1,3-tetranitropropane (136) and 1,1,1,3-tetranitrobutane respectively. A number of examples of additions of 1,1-dinitroethane, 1,1-dinitropropane and 1,1-dinitrobutane to nitroalkenes have been reported. Feuer and co-workers reported the synthesis of 1,3,3,6,6,8-hexanitrooctane (137) from the reaction of 1,1,4,4-tetranitrobutane (30) with nitroethene under basic conditions. 

Frankel synthesized 2-nitro-3-acetoxy-l-propene (139) by heating l,3-diacetoxy-2-nitropropane (138) with sodium acetate under reduced pressure. The reaction of 2-nitro-3-acetoxy-l-propene with 1,1-dinitroethane yields 2,2,4,6,6-pentanitroheptane. The same reaction with nitroform provides 1,1,1,3,5,5,5-heptanitropentane (142), a powerful explosive (VOD 9230 m/s) with an excellent oxygen balance. The synthesis of 1,1,1,3,5,5,5-heptanitropentane from2-nitro-l,3-propanediol and 2-nitro-l-propen-3-ol has also been reported and involves a similar mechanism. 

Reactions are very dependent on the nature of the base and the reaction conditions used, for example, reaction of 1,1,1-trinitroethane with aqueous potassium hydroxide, or hydroxylamine in methanolic potassium methoxide, gives high yields of potassium 1,1-dinitroethane. ° However, reaction of 1,1,1-trinitroethane with potassium ethoxide, potassium methoxide and ethanolic potassium cyanide is reported to give 2,2-dinitroethylether, methyl-2,2-dinitroethylether and 3,3-dinitropropionitrile respectively, all in approximately 80 % yield via the 1,4-addition of ethoxide, methoxide and cyanide anion to 1,1-dinitroethene respectively. ... 

Primary and secondary nitroalkanes, dinitromethane, and terminal em-dinitroaliphatic compounds like 1,1-dinitroethane, all contain acidic protons and have been used to generate Mannich products. Formaldehyde is commonly used in these reactions although the use of other aliphatic aldehydes has been reported. The nitroalkane component is frequently generated in situ from its methylol derivative, a reaction which also generates formaldehyde. Ammonia, " aliphatic amines, " hydrazine, and even urea have been used as the amine component of Mannich reactions. 

As discussed above, the nitro groups of tetranitromethane and trinitromethyl compounds are susceptible to nucleophilic attack. Both potassium iodide and alkaline hydrogen peroxide affect the reductive denitration of trinitromethyl groups to em-nitronitronates 1,1,1-trinitroethane (33) is quantitatively reduced to potassium 1,1-dinitroethane (24) on treatment with alkaline hydrogen peroxide. Nucleophiles such as potassium fluoride in DMF can displace nitrite anion from tetranitromethane. Various nucleophiles, including azide, chloride, fluoride and ethoxide have been used to displace one of the nitro groups from fluorotrinitromethane. 

Pentanitroheptane. CH3C(N02)2CH2-CH(N02)CH2C(N02)2CH3 mw 325.23, N 21.54%, OB to C02 -46.7%. Prepd by reacting 2-nitro-3-acetoxy-l-propene with 1,1-dinitroethane... 

Hardt et al, ElectrochemTechnol 1, 375(1963) (Engl). CA 64, 3047(1966) [Prepn from 1,1-Dinitroethane (or Nitroethane) thru anodic nitration in aq 10N NaOH—10N NaNQ2 soln below RT] 13) M. Masui H. Sayo, Chem-PharmBull(Tokyo) 14(3), 306(1966) (Engl). ... 

Compound 335 has been prepd in 25 30% yield by several laboratories from either an aq soln of the K salt of 1,1-dinitroethane or a mixt... 

N 25.23%. SI yel crysts, mp 121.2-121.6°. Was prepd by Belew et al from ammonium 1-nitroethanenitronate and 1,1-dinitroethane and previous to this, it was prepd by A.D. Little labs using aa K salt of 1.1-dinitro-ethane... 

The higher intrinsic rate constant for 1,1-dinitroethane (entry 8) compared to that for CH3N02 is open to two interpretations but both are related to the steric hindrance of the coplanarity of the two nitro groups in the anion. According to the first interpretation one nitro group in the anion is planar... 

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