Nitration tetranitromethane

Except for the well-known chemicals of condensed nitric acid, nitrogen dioxide, tetranitromethane, nitrate ester, azide nitrate, and hydrogen peroxide, the synthesis method and properties of oxidizers, including hydrazine nitrate, dinitrogen tetroxide, urea perchlorate, glycol dinitrate, TNEOF, and ENEOC, will be introduced. 

The kinetics of nitration in acetic anhydride are complicated. In addition to the initial reaction between nitric acid and the solvent, subsequent reactions occur which lead ultimately to the formation of tetranitromethane furthermore, the observation that acetoxylation accompanies the nitration of the homologues of benzene adds to this complexity. 

In addition to the initial reaction between nitric acid and acetic anhydride, subsequent changes lead to the quantitative formation of tetranitromethane in an equimolar mixture of nitric acid and acetic anhydride this reaction was half completed in 1-2 days. An investigation of the kinetics of this reaction showed it to have an induction period of 2-3 h for the solutions examined ([acetyl nitrate] = 0-7 mol 1 ), after which the rate adopted a form approximately of the first order with a half-life of about a day, close to that observed in the preparative experiment mentioned. In confirmation of this, recent workers have found the half-life of a solution at 25 °C of 0-05 mol 1 of nitric acid to be about 2 days. ... 

The nitric acid used in this work contained 10% of water, which introduced a considerable proportion of acetic acid into the medium. Further dilution of the solvent wnth acetic acid up to a concentration of 50 moles % had no effect on the rate, but the addition of yet more acetic acid decreased the rate, and in the absence of acetic anhydride there was no observed reaction. It was supposed from these results that the adventitious acetic acid would have no effect. The rate coefficients of the nitration diminished rapidly with time in one experiment the value of k was reduced by a factor of 2 in i h. Corrected values were obtained by extrapolation to zero time. The author ascribed the decrease to the conversion of acetyl nitrate into tetranitromethane, but this conversion cannot be the explanation because independent studies agree in concluding that it is too slow ( 5.3.1). 

Nitronaphthalene. 1-Nitronaphthalene is manufactured by nitrating naphthalene with nitric and sulfuric acids at ca 40—50°C (37). The product is obtained in very high yield and contains ca 3—10 wt % 2-nitronaphthalene and traces of dinitronaphthalene the product can be purified by distillation or by recrystaUization from alcohol. 1-Nitronaphthalene is important for the manufacture of 1-naphthalenearnine. Photochemical nitration of naphthalene by tetranitromethane in dichioromethane and acetonitrile to give 1-nitronaphthalene has been described (38). 

Nucleophilic displacement of iodide by the nitrite ion in 1-iodo-17/. l//,2//,2W-perfluoroalkanes affords the 1-nitro analogue (equation 4). Oxidative nitration of the 1-mtro-l//, l//,2//.2//-perfluoroalkane with tetranitromethane yields the ge/n-dinitro compound [4. ... 

Cyclic and acyclic silyl enol ethers can be nitrated with tetranitromethane to give ct-nitro ketones in 64-96% yield fEqs. 2.42 and 2.43. " The mechanism involves the electron transfer from the silyl enol ether to tetranitromethane. A fast homolydc conphng of the resultant cadon radical of silyl enol ether with NO leads tn ct-nitro ketones. Tetranitromethane is a neutral reagent it is commercially available or readdy prepared. " ... 

Several lesser known nitrating agents, which have been used on a lab scale are metal nitrates in the presence of acetic acid or acetic anhydride, tetranitromethane and hexanitroethane in an alkaline medium, and nitroguanidine in soln in sulfuric acid, used for the nitration of aromatic... 

In the purification of TNT the following impurities have to be removed (1) traces of nitric and sulfuric acids (2) unsymmetrical isomers (3) products of incomplete nitration (4) byproducts (tetranitromethane, trinitrobenzene, nitrobenzoic acids, nitrocresols, etc)... 

Nitromethane is very likely to detonate when aluminium powder is present. The same is true for a tetranitromethane/aluminium mixture. With aromatic nitrated derivatives, and in particular commercial explosives, the mixture with aluminium does not represent any danger. However, adding a drop of water causes spontaneous ignition that takes place within a time limit depending on quantities. 

This intermediate, produced by action of alkali on tetranitromethane, must be kept damp and used as soon as possible with great care, as it may be explosive [1], Material produced as a by-product in a nitration reaction using tetranitromethane was washed with acetone. It exploded very violently after several months storage [2],... 

Cyclic nitroalkenes are prepared from cyclic ketones via nitration of vinylstannanes with tetranitromethane in DMSO, as shown in Eq. 2.36, where DMSO is a critical choice of solvent for replacing tin by nitro at the unsaturated carbon. The conversion of ketones to vinylstannanes... 

Tetranitromethane Phenolic Group Nitration at Ortho Position... 

Figure 19.22 Phenolic compounds may be derivatized to contain reactive diazonium groups by nitration with tetranitromethane followed by reduction with sodium dithionite and diazotization with sodium nitrite in dilute HCI.

Vincent, J.P., Lazdunski, M., and Delaage, M. (1970) Use of tetranitromethane as a nitration reagent. Reaction of phenol sidechains in bovine and porcine trypsinogens and trypsins. Eur. ]. Biochem. 12, 250. 

Having shown that the enol silyl ethers are effective electron donors for the [D, A] complex formation with various electron acceptors, let us now examine the electron-transfer activation (thermal and photochemical) of the donor/ acceptor complexes of tetranitromethane and quinones with enol silyl ethers for nitration and oxidative addition, respectively, via ion radicals as critical reactive intermediates. 

Nitration of enol silyl ethers with tetranitromethane... 

In a similar vein, various electron acceptors yielding anion radicals that undergo rapid unimolecular decomposition also facilitate the efficacy of Scheme 1 by effectively obviating the back-electron transfer. For example, the nitration of enol silyl ether with tetranitromethane (TNM) occurs rapidly (despite an unfavorable redox equilibrium)78 owing to the fast mesolytic fragmentation of the TNM anion radical79 (Scheme 15). 

Note that this provides an alternative to tetranitromethane for nitration of propenylbenzenes, and an alternative to lithium aluminum hydride or Zn-Hg for reduction of nitropropenes. 

Charge-transfer nitration of aromatic donors with tetranitromethane 237 Simultaneous electrophilic and charge-transfer nitration of aromatic donors with A-nitropyridinium ion 241... 

CHARGE-TRANSFER NITRATION OF AROMATIC DONORS WITH TETRANITROMETHANE... 

As useful as tetranitromethane is as a charge-transfer nitrating agent, it is generally too unreactive to effect the comparable electrophilic nitration of most aromatic donors, except the most electron-rich ones. Thus in order to make the direct comparison between the photochemical and thermal nitration of the same ArH, we now turn to the A-nitropyridinium acceptor (PyNOj) as the alternative nitrating agent (Olah et al., 1965, 1980). For example, PyNO can be readily prepared as a colourless crystalline salt, free of any adventitious nitrosonium impurity, and used under essentially neutral conditions. Most importantly, the electrophilic reactivity of this... 

Nitration of naphthalene216, phenol derivatives217, dibenzofuran218 and 1,2,3,4-tetramethylbenzene219 occurs in a similar way, by charge-transfer excitation of complexes of naphthalene derivatives with A-nitropyridinium or tetranitromethane acceptors. The... 

The nitration reagents (NO2 Y) for electrophilic aromatic nitration span a wide range and contain anions Y such as nitric acid (Y = OH-), acetyl nitrate (Y = OAc-), dinitrogen pentoxide (Y = NO3-), nitryl chloride (Y = Cl-), TV-nitropyridinium (Y = pyridine) and tetranitromethane [Y = C(N02)3-]. All reagents contain electron-deficient species which can serve as effective electron acceptors and form electron donor-acceptor (EDA) complexes with electron-rich donors including aromatic hydrocarbons107 (ArH, equation 86). Excitation of the EDA complexes by irradiation of the charge-transfer (CT) absorption band results in full electron transfer (equation 87) to form radical ion... 

Nitration with tetranitromethane proceeds along the ion-radical ronte. Tetranitromethane is a smooth nitrating agent and mild oxidizer. It is convenient for nitration of highly activated snbstrates snch as phenols, azulene, and heterocycles in the presence of pyridine, N,iV-dialkylaniline, etc. As shown (Morkovnik 1988), these reactions inclnde one-electron transfer ... 

The reaction of alkynes with nitric acid or mixed acid is generally not synthetically useful. An exception is the reaction of acetylene with mixed acid or fuming nitric acid which leads to the formation of tetranitromethane. A modification to this reaction uses a mixture of anhydrous nitric acid and mercuric nitrate to form trinitromethane (nitroform) from acetylene. Nitroform is produced industrially via this method in a continuous process in 74 % yield. " The reaction of ethylene with 95-100 % nitric acid is also reported to yield nitroform (and 2-nitroethanol). The nitration of ketene with fuming nitric acid is reported to yield tetranitromethane. Tetranitromethane is conveniently synthesized in the laboratory by leaving a mixture of fuming nitric acid and acetic anhydride to stand at room temperature for several days. ... 

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