4- Methoxy-1-nitro

Trinitro Methyl Anisole (4,6-Dinitro-2-nitro-methyl-anisole, 3,5-Dinitro-6-methoxy-nitro-methyl toluol or Methyl-[4,6-dinitro-2-nitro-methyl phenyl]-ether). CH3.0.(N02)2C H2.— CH2N02, mw 257.18, N 16.34%, OB to C02 —77.77%, cryst, mp 65—66°. Prepd from 4-nitro 2-(mtromethyl)anisole by slow addition to a mixt of coned sulfuric-nitric acids (2 1) at 0° (Ref 2). Explodes violently when heated quickly (Ref 2)... 

There is considerable overlap in the effective range of the initiators, but this is less troublesome than it might seem since the various mechanisms can be expected to differ in their response to inhibitors. And if the alternatives are free radical and ion-pair with one of the possible ions not very reactive, decision is easy. For example, the polar decomposition of >-methoxy-/> -nitro benzoyl peroxide in acrylonitrile initiates... 

Cyclization of 5-methoxy(nitro)-4-hydrazinopyrimidines (485) with tri-ethyl orthoformate gave the l,2,4-triazolo[4,3-c]pyrimidine intermediate 486, which cannot be isolated due to its conversion to its [1,5-c] isomer 487 by a Dimroth rearrangement. However, the 5-benzyloxypyrimidine derivative, under the same conditions, afforded a mixture of the 8-benzyloxy derivatives of both [4,3-c] and [l,5-c]isomers 486 and 487, respectively (86TL3127 89JHC687 90H277) (Scheme 95). 

The starting substances for the synthesis of the required diphenyl ethers are suitably substituted o-nitrochlorobenzenes, which react with phenols containing in the ortho position a methoxy, nitro, or halogen group. 

Ar= alkyl, methoxy, nitro, cyano, halophenyl derivatives, 2-biphenyl... 

Kaupp and Toda performed soUd-sohd reactions by grinding together equimolar amounts of anilines and aldehydes in a mortar and keeping the mixture at room temperature for several hours or days. For instance, for quantitative conversion chloro imine required 120h, while methoxy/nitro imine needed 24h at 50°C (Scheme 3.7) [9], The rate of reaction considerably increased when these reactions are performed in ball mills. Thus, chloro and methoxy/nitro imines 36a-c can be quantitatively obtained in less than 30 min at room temperature when stoichiometric mixtures of the starting materials are ball milled. Larger runs could be performed in ball mills under heat control. 

The retention characteristics of 4,4 -disubsthuted benzanilides and benzamides (chloro, methyl, methoxy, nitro) were conducted on a Cjg column (2 = 254 nm) using a series of acetonitrile/water mobile phases [919]. The contribution of the substituent b> retention was tabulated and a predictive model for the calculation of log 2 values was presented. Mobile phase compositions from 35/65 to 70/30... 

The previous sections focused on the directing effects of a few specific groups (methyl, methoxy, nitro, and halogens). In this section, we will learn how to predict the directing effects for any substituent. That skill will prove to be essential in subsequent sections that deal with synthesis. 

Cassimjee et al. reported [22] that a variant engineered aminotransferase at TrpOOCys from Chromohacterium violaceum showed a 29-fold increase on spedfidty for synthesis of (S)-phenylethylamine and about fivefold on spedfidty for 4 -substituted acetophenones, where the groups at 4 position were bromo, chloro, hydroxy, methoxy, nitro, methyl, and cyano. The amine donor was isopropylamine. The reaction schemes are shown in Figure 7.5. 

The similarity of their rate profiles, and the similarity of their rate constants for nitration at a particular temperature and acidity show that 4-pyridone, i-methyl-4-pyridone, and 4-methoxypyridine are all nitrated as their cations down to about 85 % sulphuric acid. The same is true of 2-methoxy-3-methylpyridine. In contrast, 3- and 5-methyl-2-pyridone, i,5-dimethyl-2-pyridone and 3-nitro-4-pyridone all react... 

A mixture of 3-methoxy-2-nitro-P-pyrrolidinostyrene (lOg, 40 mmol) and Raney nickel (25 g) in methanol-THF (40 ml of each) was heated to 60"C and,... 

Pigment Red 23 [6471494] 12355 N aphthol AS coupling of dia2oti2ed 2- methoxy-5-nitro-ani1ine with 3- hydro xy-2 -naphth-3 -nitroanihde... 

Pigment YeUow 74 [6358-31-2] 11741 monoa2o coupling of dia2oti2ed 2-methoxy-4-nitro-ani1ine with a ceto a cet- 2-m eth oxyan i1 i de... 

Many of the pigments carry a nitro group ia the diazonium component, usually ia the ortho position (R = NO2). Among the acetoacetaryUde components the o-methoxy derivative (R2 = OCH, R3 = H) is one of the most important ia the production of azo pigments. The colors of these pigments range from red to green-shade yellows. Commercially important products ate shown ia Table 3. 

Nucleophilic aromatic substitutions involving loss of hydrogen are known. The reaction usually occurs with oxidation of the intermediate either intramoleculady or by an added oxidizing agent such as air or iodine. A noteworthy example is the formation of 6-methoxy-2-nitrobenzonitrile from reaction of 1,3-dinitrobenzene with a methanol solution of potassium cyanide. In this reaction it appears that the nitro compound itself functions as the oxidizing agent (10). 

Alkoxyl tion. The nucleophilic replacement of an aromatic halogen atom by an alkoxy group is an important process, especially for production of methoxy-containing iatermediates. Alkoxylation is preferred to alkylation of the phenol wherever possible, and typically iavolves the iateraction of a chloro compound, activated by a nitro group, with the appropriate alcohol ia the presence of alkaU. Careful control of alkaU concentration and temperature are essential, and formation of by-product azoxy compounds is avoided by passiag air through the reaction mixture (21). 

When large groups, such as phenyl, bromo, ethoxycarbonyl or nitro are attached at position 3, the principal products are l-alkylcinnolin-4(l/f)-ones. Cyanoethylation and acetylation of cinnolin-4(l/f)-one takes place exclusively at N-1. Phthalazin-l(2/f)-ones give 2-substituted derivatives on alkylation and acylation. Alkylation of 4-hydroxyphthala2in-l(2/f)-one with an equimolar amount of primary halide in the presence of a base leads to 2-alkyl-4-hydroxyphthalazin-l(2/f)-one and further alkylation results in the formation of 4-alkoxy-2-alkylphthalazinone. Methylation of 4-hydroxy-2-methyl-phthalazinone with dimethyl sulfate in aqueous alkali gives a mixture of 4-methoxy-2-methylphthalazin-l(2/f)-one and 2,3-dimethylphthalazine-l,4(2//,3//)-dione, whereas methylation of 4-methoxyphthalazin-l(2/f)-one under similar conditions affords only 4-methoxy-2-methylphthalazinone. 

The 3-, 4-, 5- and 6-positions in the pyridazine nucleus are electron deficient due to the negative mesomeric effect of the nitrogen atoms. Therefore, electrophilic substitution in pyridazines is difficult even in the presence of one or two electron-donating groups. The first reported example is nitration of 4-amino-3,6-dimethoxypyridazine to yield the corresponding 5-nitro derivative. Nitration of 3-methoxy-5-methylpyridazine gives the 6-nitro-,... 

Pyridazine 1-oxides substituted at position 3 or positions 3 and 6 afford the corresponding 5-nitro derivatives. A methyl group at position 6 (a with respect to the iV-oxide group) is frequently converted into the cyano group, and a methoxy group at position 6 is demethy-lated by benzoyl chloride/silver nitrate. For example, 3-substituted 6-methylpyridazine 1-oxides give the 5-nitro derivatives (96) and the 6-cyano-5-nitro derivatives (97), whereas... 

Hydroxyaminopyridazine 1-oxides are usually formed by catalytic hydrogenation of the corresponding nitro derivatives over palladium-charcoal in methanol, provided that the reaction is stopped after absorption of two moles of hydrogen. 3-Hydroxyaminopyridazine 1-oxide and 6-amino-4-hydroxyamino-3-methoxypyridazine 1-oxide are prepared in this way, while 5-hydroxyamino-3-methylpyridazine 2-oxide and 5-hydroxyamino-6-methoxy-3-methylpyridazine 2-oxide are obtained by chemical reduction of the corresponding nitro compounds with phenylhydrazine. 

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