Reaction with aromatic nitro compounds

W.E. Griffiths, G.F. Longster, J. Myatt and P.F. Todd, Electron spin resonance studies of electron-transfer reactions with aromatic nitro-compounds in aqueous media, J. Chem. Soc. (B), (1966) 1130. 

The oxidation of 16 to quinacridone can be accomplished by several methods including reaction with aromatic nitro compounds in the presence of base in aqueous alcohol solvents [13], by interaction with dioxygen (introduced by air injection) [14] or by contact with hydrogen peroxide [15]. Also, dehydrogenation can be accomplished by interaction with various quinones such as anthraquinone-2-sulfonic acid [16] or by contact with suitable catalysts such as palladium-charcoal [17]. Successful oxidation is exemplified by the production of chemically and crys-tallographically pure quinacridone products. 

Attempts have been made to develop methods for the production of aromatic isocyanates without the use of phosgene. None of these processes is currently in commercial use. Processes based on the reaction of carbon monoxide with aromatic nitro compounds have been examined extensively (23,27,76). The reductive carbonylation of 2,4-dinitrotoluene [121 -14-2] to toluene 2,4-diaLkylcarbamates is reported to occur in high yield at reaction temperatures of 140—180°C under 6900 kPa (1000 psi) of carbon monoxide. The resultant carbamate product distribution is noted to be a strong function of the alcohol used. Mitsui-Toatsu and Arco have disclosed a two-step reductive carbonylation process based on a cost effective selenium catalyst (22,23). 

A variety of natural products and pharmaceutical agents contain a tetrahydroquinoline moiety [31]. Recently, a simple and general access to these heterocycles by a so-far unknown domino reaction of aromatic nitro compounds 7-65 and 2,3-dihydrofuran mediated by indium in water has been described by Li and coworkers (Scheme 7.19) [32]. It is assumed that the process is initiated by reduction of the nitro group in 7-65 to give the aniline 7-66 on treatment with indium in... 

The Sundberg indole synthesis using aromatic azides as precursors of nitrenes has been used in synthesis of various indoles. Some kinds of aryl azides are readily prepared by SNAr reaction of aromatic nitro compounds with an azide ion. For example, 2,4,6-trinitrotoluene (TNT) can be converted into 2-aryl-4,6-dinitroindole, as shown in Eq. 10.60.83... 

Addition of organometallic reagents to nitro compounds is possible but is sparingly used. Reaction of aromatic nitro compounds with large excess of phenyl magnesium bromide produces hydroxylamines in moderate yield . Similar addition of Grignard compounds to nitromethane proceeds in low yield ° while addition of excess methyllithium to tertiary nitro compound 113 results in formation of hydroxylamine 114 (equation 83) . ... 

The high-temperature reaction of aromatic amines with aromatic nitro compounds in the presence of base affords primarily an azo compound [39,40]. Because two independent laboratories have reported reasonable results with this synthesis, the procedure is given here. To be noted is that, while the reaction as described here involves 2-naphthylamine, a known carcinogenic intermediate, it is given only for reference to the procedure. Evidently, other aromatic amines also undergo the reaction. 

Aromatic nitroso compounds combine with primary arylamines in glacial acetic acid to give symmetrical or unsymmetrical azo compounds (the Mills reaction).554 A wide variety of substituents may be present in both aryl groups. Unsymmetrical azo compounds have also been prepared by the reaction between aromatic nitro compounds ArN02 and N-acyl aromatic amines Ar NHAc.555 The use of phase transfer catalysis increased the yields. 

Coordination chemistry reveals how two ArN species can be coupled into one azobenzene molecule. In the case of the reaction of Fe3(CO)12 with aromatic nitro compounds in benzene1161, formation of derivatives such as in structure 111 has been proven by X-ray diffraction. Azoxybenzene can be formed by reaction of nitrene with nitrosobenzene, formed by reduction of nitrobenzene. 

B. Survey of the Reactions of Aromatic Nitro-Compounds with Bases... 

One of the typical reactions of aromatic nitro compounds with two or more nitro groups is that with sodium sulphite. Here one of the nitro groups is replaced by a sulphonic group (as its sodium salt) and sodium nitrate is formed ... 

Aromatic urethanes and dialkyl carbonates were simultaneously prepared by the reaction of aromatic nitro compounds with alcohols and carbon monoxide over a catalyst mixture containing DBU (82JAP(K)32251). 

Action of bases in nucleophilic reactions of nitro compounds Action of Grignard reagent on nitro aimpounds Reaction of aromatic nitro compounds with diazomethane... 

Recently Bartoli and co-workers [85-87] have published a number of papers dedicated to the systematic study of the reaction of aromatic nitro compounds with Grignard reagent. They confirmed the nucleophilic character of the alkylation of the ring. They also found that under their experimental conditions the nitro group was reduced to the nitroso group (17) ... 

Some of the main reactions of aromatic nitro compounds with free radicals given here [116]. Nitrobenzene reacts with hydroxyl produced by hydrogen iroxide ferrous salt reaction (28)... 

REACTION OF AROMATIC NITRO COMPOUNDS WITH DIAZOMETHANE... 

Reaction of the carbanion derived from 1,3-dithiane 1,1-dioxide with aromatic nitro compounds results in oxidative nucleophilic substitution of hydrogen rather than SnAt displacement of even halogen (94T4913). 

Visentin, F. (2005) Kinetic study of hydrogenation reactions of aromatic nitro compounds using a new pressure resistant reaction calorimeter combined with a FTIR-ATR device. Dissertation, ETH, Zurich, No. 16053. 

By reaction in benzene of P 3aromatic nitro compounds, derivatives such as <1) and <3) reacts with Ru3ruthenium nitrene complex <5) reaction with excess nitrobenzene in boiling benzene [653. On the other hand even the thermal disproportionation of <5) (M=sRu R=Ph) under an inert atmosphere and in solution leads to the formation of <1), and other as yet uncharacterised products[663. Complexes following sequence of reactions]603s... 

The complexes [react with aromatic nitro compounds in toluene at room temperature same oxo-imido derivatives obtained by reaction with the correspond ng aromatic nitroso derivatives (eq. 21) (53]. This suggests that n i trosobenzenes are intermediates in the conversion o-f nitro compounds to the binuclear metal 0x0 complexes. These complexes by reaction with NaOH under phase trans-fer conditions give the corresponding aromatic ami nes. 

Nitrobiphenyl gave 2-aminobiphenyl, but no carbazole therefore a nitrene intermediate appeared unlikely in this reduction. The reaction between Kj[HFe(CO)43 and aromatic nitro compounds proceeds vigorously and exothermally in alcohol at room temperature to give the corresponding aromatic amines in excellent yields[76j. The reaction is not catalytic and is not affected by reaction atmospherearomatic nitro compounds with Fe3methanol-benzene is catalysed by the crown ether, 18 crown-6, with aqueous K0H[77j, or by PhCH2N3+Cl " with aqueous NaOH[64,78l. 

Reaction of aromatic nitro compounds with pentacyano-cobaltate(II)/ 0.667 molar KOH in H2O... 

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