Nitro, acids xylenes

Titanium ions can also he used as redox catalysts for the indirect cathodic reduction of nitro compounds (417). The electroreduction is carried out in an H20-H2S04/Ti(S04)2-(Pb/Cu) system at 45 80°C under 5 20Am . Nitrobenzene, dinitrobenzene, nitrotoluene, 2,4-dinitrotoluene, 2-nitro-m-xylene, nitro-phenol, 2,4-dinitrophenol, nitrophenetole, o-nitroanisole, 4-nitrochlorotoluene, ni-trobenzenesulfonic acid, and 4,4 -dinitro-stilbene-2,2 -disulfonic acid can all be reduced by this procedure to the corresponding amino compounds (418) in good yields (Scheme 146) [513-516]. Tin... 

Chemical/Physical. Under atmospheric conditions, the gas-phase reaction of o-xylene with OH radicals and nitrogen oxides resulted in the formation of o-tolualdehyde, o-methylbenzyl nitrate, nitro-o-xylenes, 2,3-and 3,4-dimethylphenol (Atkinson, 1990). Kanno et al. (1982) studied the aqueous reaction of o-xylene and other aromatic hydrocarbons (benzene, toluene, w and p-xylene, and naphthalene) with hypochlorous acid in the presence of ammonium ion. They reported that the aromatic ring was not chlorinated as expected but was cleaved by chloramine forming cyanogen chloride. The amount of cyanogen chloride formed increased at lower pHs (Kanno et al., 1982). In the gas phase, o-xylene reacted with nitrate radicals in purified air forming the following products 5-nitro-2-methyltoluene and 6-nitro-2-methyltoluene, o-methylbenzaldehyde, and an aryl nitrate (Chiodini et ah, 1993). 

Nitrous acid, see Dimethylamine Nitrous oxide, see Aldicarb. Atrazine. Chloropicrin Nitro-o-xylenes, see oXylene Nitro-ro-xylenes, see ro-Xylene Nitryl chloride, see Formaldehyde y-Nonachlor, see Heptachlor 2,2, 3,3, 4,4, 5,5, 6-Nonachlorobiphenyl, see Pentachlorobenzene... 

Dinitro-l, 2-dime tbylbenzene, ndls (from ale), mp 56—60° 89—90° obtd with other products on nitrating o-xylene or 3-nitro-o-xylene with coned nitric acid (Ref 1, p369 Ref 2, pl8l)... 

Nitroxylenes are especially important because 4-amino-o-xylene (xylidine), formed from 4-nitro-o-xylene (4-o-NX) upon reduction, is used as a starting material for the production of riboflavin. Nitration of o-xylene by the conventional mixed acid method gives a mixture of 4-o-NX 31-55% and 3-o-NX 45-69 %. 

Patil, P. T., Malshe, K. M., Dagade, S. P. and Dongare, M. K. Regioselective nitration of o-xylene to 4-nitro-o-xylene using nitric acid over solid acid catalysts. Catal. Commun., 2003, 4, 429-434. 

Nitro-p-xylene, reduced in concentrated sulphuric acid, gives the corresponding amidoxylenol (Gattermann and Heider3) ... 

Nitro-toluic acid—Nitro-terephthalic acid — Nitro-iso-phthalic acjd—aiai-Nitro-naphthalene>sulphonic acid...63-65 Reaction of Gattermann — Nitro-toluenes—Nitro-p-xylene— Ldb s experiments — Aromatic nitramines — Nitro-car-boxylic acids—Nitro-sulphonic acids—Nitro-derivatives... 

Cydopentane reagents used in synthesis are usually derived from cyclopentanone (R.A. Ellison, 1973). Classically they are made by base-catalyzed intramolecular aldol or ester condensations (see also p. 55). An important example is 2-methylcydopentane-l,3-dione. It is synthesized by intramolecular acylation of diethyl propionylsucdnate dianion followed by saponification and decarboxylation. This cyclization only worked with potassium t-butoxide in boiling xylene (R. Bucourt, 1965). Faster routes to this diketone start with succinic acid or its anhydride. A Friedel-Crafts acylation with 2-acetoxy-2-butene in nitrobenzene or with pro-pionyl chloride in nitromethane leads to acylated adducts, which are deacylated in aqueous acids (V.J. Grenda, 1967 L.E. Schick, 1969). A new promising route to substituted cyclopent-2-enones makes use of intermediate 5-nitro-l,3-diones (D. Seebach, 1977). 

A solution of trifluoroacetic acid in toluene was found to be advantageous for cydization of pyruvate hydrazoncs having nitro substituents[4]. p-Toluene-sulfonic acid or Amberlyst-15 in toluene has also been found to give excellent results in preparation of indole-2-carboxylale esters from pyruvate hydra-zoiies[5,6J. Acidic zeolite catalysts have been used with xylene as a solvent to convert phenylhydraziiies and ketones to indoles both in one-flask procedures and in a flow-through reactor[7]. 

C. MEDINA. The crude methylenedi(nitro-formamide) is pressed dry on the filter, stirred into lOSml of formic acid, and the paste allowed to stand overnight. The next day the soln is filtered thru an acid-proof flit, the formic acid and w removed by codistn with xylene, and the crude MEDINA, which seps as a sand, filtered and dried over paraffin and NaOH in a vacuum yield 80—100% based on methylene diform-amide, mp 98—103°. The crude MEDINA is recrystd from 2-nitropropane or et chloride iso-Pr ale 9 1, mp 104-059 (Ref 11, p 54). This prepn is also covered in Ref 20... 

OB to C02 —85.04%, needles from glac AcOH, mp 262—63° (decomp). Sol in glac AcOH, acet, dioxane py si sol in benz, toluene, xylene amyl ale. Prepn from l-nitro-2-. me thy lnaphthalene by nitration using mixed acids of nitric (d 1.52g/cc), sulfuric (d 1.84 g/cc) oleum (20—25% SO5 free), and heating for one hour at 80° on a water bath. Two other isomers which do not decompose are prepd simultaneously viz, mp (I) 230° ... 

Toxicity. Picric Acid is more toxic than the nitro derivatives of toluene, xylene or naphthalene. It is, however, much less toxic than nitro derivatives of benzene... 

Pyrazoles were synthesized in the authors laboratory by Le Blanc et al. from the epoxy-ketone as already stated in Sect. 3.1.1a, Scheme 35 [80]. The synthetic strategy employed by Le Blanc et al. [80] was based upon that the strategy published by Bhat et al. [81] who also described the synthesis of pyrazoles but did not report cytotoxic evaluation on the synthesized compounds. Scheme 48 shows the synthesis of the most active compound (178). Dissolution of the epoxide (179) with a xylenes followed by treatment with p-toluenesulfonic acid and hydrazine hydrate produced the pure nitro-pyrazole 180 in good yield (60%). Catalytic hydrogenation with palladium on activated carbon allowed the amino-pyrazole (178) to be obtained in a pure form. This synthesis allowed relatively large numbers of compounds to be produced as the crude product was sufficiently pure. Yield, reaction time, and purification compared to reported approaches were improved [50, 61, and 81]. Cytotoxicity of these pyrazole analogs was disappointing. The planarity of these compounds may account for this, as CA-4, 7 is a twisted molecule. 

Nitro-2-hydrazinotoluene, It golden-yel or orn-yel ndls with a violet tinge (from ale), mp 179-80° diffc sol in hot ale xylene was prepd by heating the K salt of N-[4-Nitro-2-methyl-phenyl] -hydrazine-N,N -disul-fonic acid with coned HC1 (Refs 1 3) 3-Nitro-4-hydmzinotoluene, dk-red ndls (from eth), mp 110—11° v sol in acet sol in eth, chlf benz si sol in petr eth was prepd by diazotizing 2-nitro-4-methylaniline with Zn chloride HC1. Its Hydrochloride salt, C7H9N3O2+HCI, orn-red ndls or plates (from w) dec at 190-91° (Refs 2 4)... 

Nitro Derivatives of Diazoxylenesulfonic Acid 2-Nitro-6-diazo-m xylene-4-sulfonic Acid,... 

B is-( 3-nitrophenyl)-furoxan, ndls (from glac acet ac or acet) yel ndls (from xylene), mp 183—85° readily sol in hot xylene, warm glac acet ac St acetone insol in w, ale, eth, petr eth, benz St chlf was prepd by oxidation of 3-nitro-a-benzaldoxime with isoamyl-nitrice in hot benz, or by shaking it. with benzoic acid or m-nitrobenzoic acid Ag salt in eth and by other methods (Refs 2, 3, 4,... 

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