Nitronaphthalenes, reaction with

The deoxygeneration of nitroarenes by trivalent phosphorus compounds in the presence of amines is a useful route to 3/f-azepin-2-amines (cf. compounds 32, Section 3.1.1.4.2.2.). Subsequently, it has been shown, by carrying out the reaction in strongly basic solution, that the process can be extended to the synthesis of 1H-. 3H- and 5//-2-benzazepines from nitronaph-thalenes 43 For example, 1-nitronaphthalenes 3 with dimethyl phosphite in the presence of sodium methoxide and a primary or secondary aliphatic amine, yield the dimethyl 5//-2-ben-zazepin-3-yl phosphonates 4 accompanied, in some cases, by the isomeric 3//-2-bcnzazepin-3-yl phosphonates 5. 

The transformation of arenes in the troposphere has been discussed in detail (Arey 1998). Their destruction can be mediated by reaction with hydroxyl radicals, and from naphthalene a wide range of compounds is produced, including 1- and 2-naphthols, 2-formylcinnamaldehyde, phthalic anhydride, and with less certainty 1,4-naphthoquinone and 2,3-epoxynaphthoquinone. Both 1- and 2-nitronaphthalene were formed through the intervention of NO2 (Bunce et al. 1997). Attention has also been directed to the composition of secondary organic aerosols from the photooxidation of monocyclic aromatic hydrocarbons in the presence of NO (Eorstner et al. 1997) the main products from a range of alkylated aromatics were 2,5-furandione and the 3-methyl and 3-ethyl congeners. 

To enter the Barton-Zard condensation, a substrate must have essentially nitro-alkene character. This is the reason why the reaction with nitrobenzene fails and 1-nitronaphthalene also reacts slightly (94CC1019). An additional N02 group on the naphthalene ring substantially facilitates the transformation but the expected dipyrroles are not formed (95TL4381). Table 2 presents various substrates, the corresponding products and some other details of the Barton-Zard condensation. 

On the other hand Price and Sears [107] studied the reactions of nitryl chloride with various aromatic compounds in the presence of aluminium chloride, and found that phenol, anisole and naphthalene tended to undergo oxidative degradation. In the case of naphthalene they obtained a 31% yield of a- nitronaphthalene, whereas with anisole and phenol they were able to isolate only traces of nitro compounds without any evidence of chlorination. 

Methoxy-l-nitronaphthalene (73a) and 1-nitronaphthalene (73b) undergo photochemical aromatic substitution reactions with cyanide (Scheme XXVIII). A two-fold increase in the quantum yield for the reaction is observed for (73a) when the reaction occurs in HDTC1 compared to aqueous solution 73). However, a 6800-fold catalytic increase in quantum yield is observed for (73b). SDS micelles decrease the quantum yield compared to aqueous solutions. The higher local concentration of cyanide near the HDTC1 micelles can explain a least partially the increase in quantum yield. However, the 6800-fold increase for (73b) is also due to a polarity effect on the reaction. This was demonstrated by an increase in the quantum yield of the reaction with decreasing polarity. 

SAFETY PROFILE Poison by ingestion. Moderately toxic by intraperitoneal route. A skin, eye, and mucous membrane irritant. A flammable solid when exposed to heat or flame. To fight fire, use CO2, dry chemical, or water spray. Explosive reaction with nitric acid + sulfuric acid above 60° C. Forms a sensitive explosive mixture with tetranitromethane. When heated to decomposition it emits toxic fumes of NOx. See also 1-NITRONAPHTHALENE, 2-NITRONAPHTHALENE, and NITRO COMPOUNDS OF AROMATIC HYDROCARBONS. 

NITRATING ACID [legal label name for various concentrations of sulfuric and nitric acid mixtures (mixed acid often 61% sulfuric/36% nitric)]. A strong oxidizer. Violent reaction with reducing agents, bases, 1,2-dimethyl-2-trimethylsilylhydrazine, phthalic anhydride, lithium-2,2-dimethyltrimethylsilyl hydrazide, nitronaphthalene, organic solvents, and other organic materials. Violent reaction when water is added to acid to dilute, always add acid to water. See Nitric Acid and Sulfuric Acid. 

The same authors reported that the reaction of nitronaphthalenes 73 with guanidines in the presence of t-BuOLi gave amino-1,2,4-triazines 74 fused with naphthalene [65] (Scheme 36). 

PhotochemicaUy, NO2 has been produced directly from nitrite or via the nitrite reaction with the triplet state of nitronaphthalene [86, 88]. 

Ried and his group have continued their work with benzo[6]thiophen derivatives, and have shown that they may be converted to a number of heterocycles [e.g. (267) and (268)] upon reaction with dicyclohexyl carbodi-imide and cyanamides. Some Japanese workers have followed up an earlier report concerning nitroquinolines with an interesting reaction in the naphthalene series. The potassium salt (269), which is formed from 2-nitronaphthalene cyclizes on treatment with HCl to give naphtho-l,3-oxazines (270), and these in turn can be further modified. 

Moreover, when the dinitronaphthalenes 70 and 71 reacted with isopaene (60°C, 24 h) in the presence of EAN or [HMIM][BF4], they generated a mixture of phenanthrenes and N-naphthylpyrroles with different 5deld ratios and a moderate predominance of the normal DA product. In the case of 1,3-dinitronaphthalene 70, newly a clear tendency towards the DA cycloaddition to the C3-C4 bond was observed. In the reactions with isoprene, 1,3-dinitronaphthalene gave the corresponding 2-metil-lO-nitro-phenanthrene (32%), together with [3-methyl-l-(l-nitronaphthalen-3-yl)-pyrrole] and [3-methyl-l-(2-nitronaphthalen-4-yl)-pyrrole]. On the other hand, the reactions of 1,4-dinitronaphthalene with isoprene afforded 2-methyl-9-nitrophenantrene (27%) and 3-methyl-l-(4 -nitronaphtalene-l -iy)-pyrrole. 

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