A- nitromethane

The use of other compounds as joint solvents, for instance, often makes these unstable compounds sensitive. So, a nitromethane/acetone mixture is a very sensitive explosive. 

A nitromethane/aluminium chloride complex had been prepared. A gaseous alkene was added to the complex the pressure reached 5.6 bar and the temperature 2°C. The medium had been stirred at the beginning of the operation and then intemupted. A temperature rise caused the autoclave to detonate and the medium to carbonise entirely. 

N-Methylethylamine has been prepared by heating ethyl-amine with methyl iodide in alcohol at 100° 3 by the hydrolysis of N-methyl-N-ethylarenesulfonamides,4-5 -nitroso-N-methyl-N-ethylaniline,6 or methylethylbenzhydrylidene ammonium iodide 7 by catalytic hydrogenation of ethyl isocyanate or ethyl isocyanide 8 and by the reduction of ethyl isocyanate by lithium aluminum hydride,9 of N-methylacetisoaldoxime by sodium amalgam and acetic acid,10 or of a nitromethane/ethylmagnesium bromide adduct by zinc and hydrochloric acid.11... 

For the cyclization of dialdehydes, however, its utility seems limited. Being a nitromethane addition product, it can readily undergo retro-nitromethane addition with alkali to give formaldehyde and nitromethane. Thus, it is not surprising that reaction of glutaraldehyde with 2-nitroethanol under the usual conditions (i.e. 1 molar equivalent of sodium hydroxide in aqueous ethanol) should yield 2-nitrocyclohexane-1,3-diol 5), a nitromethane cyclization product With catal5dic amounts of sodium hydroxide (pH 8—9), however, 1-hydroxymethyl-l-nitro-cyclohexane-2-6-diol (80) can be isolated in yields of 24—29%... 

The electrochemical oxidation of 2,3,4,5-tetraanisylpyrrole (121) in nitromethane at the second wave resulted in the formation of a cation, the reaction of which depended on the reaction temperature [Eq. (88)]. At 15°C a 90% yield of 2-hydroxy-2,3,4,5-tetraanisylpyrrole (122) was formed, whereas at 90°C the major product resulted from incorporation of a nitromethane molecule into the ring, giving a tetraanisylpyridine (123a or 123b)177 [Eq. (88)]. 

Figure 7-11. A cartoon representation of the multi-component assembly of an encapsulating ligand. The white disc represents a pre-formed cap within the starting ligand and the shaded disc the new cap that has been built from a number of components. For example, in the ligand 7.9, the shaded cap is built from three formaldehyde molecules and a nitromethane molecule.

It must be concluded that these experiments did not demonstrate unequivocally that a nitromethane-aldose sugar condensation had been achieved. 

Modification of metal-metal coupling is not just restricted to the inner coordination sphere. Hupp and coworkers (56) have shown that addition of the crown ethers, dibenzo-36-crown-12 (DB-36-C-12) or di-benzo-30-crown-10 (DB-30-C-10), to a nitromethane solution of the Creutz-Taube ion or crown ether oxygens for ruthenium-ammine hydrogens. Figure 5 shows the changes observed for the MMCT of effects occur with the 1 1 stoichiometry of crown ether... 

Fig. 65. Spectrum of water (bending mode) at various sili-con/electrolyte interfaces (a) nitromethane (b) acetonitrile (c) dimethyl sulphoxide. Note the progressive shift of the frequency upon increasing basicity of the solvent. (After [180]). Reprinted by permission of Elsevier Science.

There exists currently only one mention in the literature of the synthesis of a heterohexaphyrin analog. This is the hexathiahexaphyrinogen species 7.20. This macrocycle was synthesized from 2-hydroxymethyl-3,4-diethylthiophene (7.19) by heating a nitromethane solution of this monomer to reflux in the presence of the acid catalyst p-toluenesulfonic acid. In addition to a cyclic tetramer and pen tamer (cf. Chapter 6), the cyclohexamer 7.20 could be isolated in yields ranging from 0.5% to 2% (Scheme 7.1.6). Unfortunately, it was not reported whether 7.20 could be oxidized to give the corresponding aromatic derivative. 

Similar results were obtained on qiplication of the related Tiffeneau-Demjanov reaction. This semipi-nacol-type reaction, an extension of the Demjanov rearrangement, involves the rearrangement of a diazonium ion (25 Scheme 7), which is generated by the diazotization of the corresponding amino alcohol (24). The amino alcohol is obtained from the ketone by reduction of a nitromethane adduct (23a), cyanohydrin (23b) or trimethylsilyl cyanohydrin (23c). This procedure allows for a controlled addition-rearrangement sequence in cases where the use of diazomethane is complicated by the further reaction of the product ketone. 

In contrast to neutral polymer solutions, where reduced viscosity, 17sp/c, plotted against weight concentration (usually g/dL) shows a straight line (expressed by the Huggins equation) [32], the typical viscosity behavior of a polyelectrolyte solution is shown in Figure 4. This polyelectrolyte was made by quatemization of poly(styrene-co l-vinylpyridine) with n-butyl bromide [16]. The solvents used were a nitromethane/dioxane mixture. Figure 4... 

Scheme 26. Reagents and conditions a) Nitromethane, Et2NH, 0 °C, 1 hr. b) Pyridine, Ac20, 0 °C, 14 hr, 85% for 2 steps, c) Triethylphosphite, reflux, 150 min, 58%.

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