A- Nitronaphthalene

In the naphthalene series, a-naphthylamine is easily obtained by the reduction of the readily accessible a-nitronaphthalene ... 

A large red shift observed in polar solvents was indicative of the intramolecular charge transfer character of the triplet state. The change of dipole moment accompanying the transition Tj - Tn, as well as rate constants for electron and proton transfer reactions involving the T state of a-nitronaphthalene, were determined. The lower reactivity in polar solvents was attributed to a reduced n-n and increased charge transfer character of the triplet state... 

Prepare a mixtime of 40 ml. of concentrated nitric acid and 40 ml. of concentrated sulphiu-ic acid as detailed in the previous Section. Introduce 50 g. of findy-powdered naphthalene in small quantities at a time and with vigorous shaking maintain the temperatime at 45-50° and cool in ice water if necessary. When all the naphthalene has been added, warm the mixtime on a water bath at 55-60° for 30-40 minutes or until the smell of naphthalene has disappeared. Pour the mixture into 500 ml. of cold water the nitronaphthalene will sink to the bottom. Decant the liquid. Boil the solid cake with 200 ml. of water for 20 minutes and pour the water away. Transfer the oil to a large flask and subject it to steam distillation (Fig. II, 40, 1) any imattacked naphthalene will thus be removed. Pour the warm contents of the flask into a beaker containing a large volume of water which is vigorously stirred. Filter ofiF the granulated a-nitro-naphthalene at the pump, press it well, and recrystallise it from dilute alcohol. The yield of a-nitronaphthalene, m.p. 61°, is 60 g. 

Radchenko, L.G., Kitiagorodskii, A.I. (1974) Vapor pressure and heat of sublimation of naphthalene, biphenyl, octafluoronaphthalene, decafluorobiphenyl, acenaphthene and a-nitronaphthalene. Zhur. Fiz. Khim. 48, 2702-2704. 

Other factors, however, should also be effective. A specific influence of the solvent 101,116) added detergents 12 ) and remote electron donating substituents 119) has been observed. Steric hindrance, which certainly is of influence in the nucleophilic photosubstitution reactions of a-nitronaphthalenes, has been found to alter the reactivity of nitroanisoles... 

We observe that nitration of naphthalene using nitric acid-sulfuric acid gives predominantly 1-nitronaphthalene (sometimes a-nitronaphthalene), and... 

D-Mannitol hexanitrate crystallizes from ethyl alcohol in the form of needles melting at 112-113°C. Its specific gravity is 1.604. It is immiscible with water, dissolves readily in ether and hot ethanol and with difficulty in cold ethyl alcohol. With aromatic mononitro compounds, e.g. nitrobenzene, p-nitrotoluene, p-nitroanisole, a-nitronaphthalene, mannitol hexanitrate forms addition compounds melting in a non-homogeneous way, as shown by T. Urbanski [5, 6, 7, 17]. 

Naphthalene nitrates more readily than benzene, the first nitro group taking the a-position which is ortho on one nucleus to the side chain which the other nucleus constitutes. The second nitro group takes one or another of the expected positions, either the position meta to the nitro group already present or one of the a-positions of the unsubstituted nucleus. The dinitration of naphthalene in actual practice thus produces a mixture which consists almost entirely of three isomers. Ten different isomeric dinitronaphthalenes are possible, seven of which are derived from a-nitronaphthalene, seven from /3-nitronaphthalene, and four... 

None of the nitrated naphthalenes is very sensitive to shock. a-Nitronaphthalene is not an explosive at all and cannot be detonated. Dinitronaphthalene begins to show a feeble capacity for explosion, and trinitronaphthalene stands between dinitrobenzene and dinitrotoluene in its explosive power. Tetranitro-naphthalene is about as powerful as TNT, and distinctly less sensitive to impact than that explosive. Vennin and Chesneau report that the nitrated naphthalenes, charged in a manometric bomb at a density of loading of 0.3, gave on firing the pressures indicated below.46... 

Similarly, l-nitro-2-aminonaphthalene gives 1-chloronaphthalene in 69% yield and only a trace of 1-nitronaphthalene when diazotized in hydrochloric acid solution and reduced with hypophosphorous acid.83 Upon diazotization with sulfuric acid, however, a 61% yield of a-nitronaphthalene is obtained.83 The same type of side reaction occurs when 2,5-diaminotriptycene (XX) is diazotized in hydrochloric acid solution and then reduced with hypophosphorous acid.87... 

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