Preparation naphthalene

Starting with naphthalene prepare the following compounds. You may use any other monosubstituted cyclic organic molecules, any monosubstituted acyclic organic molecules containing no more than four carbons and any inorganic reagents. 

Only one oximinobis(2-pyrazolin-5-one) is known.459 This is 2,3-bis(4-oximino-3-phenyl-5-oxo-2-pyrazolin-l-yl)naphthalene prepared by nitrosation with nitrous acid. 

A coned, soln. of cholesteryl tosylate in tetrahydrofuran injected under Ng into a stirred soln. of 6 equivalents Na-naphthalene prepared from Na and naphthalene in dry tetrahydrofuran, after a few sec. when the disappearance of the green color indicates completion of the reaction a small amount of water added to convert the alkoxide salt to the alcohol cholesterol. Y 95%. — No epimeriza-... 

Diethylamine added at -30° to a soln. of Li-naphthalene prepared from Li and naphthalene in tetrahydrofuran, then crotonic acid in tetrahydrofuran added drop-wise at - 5° followed by cyclohexanone, and heated 1.5 hrs. at 60° y-(l-hydroxy-... 

Other chlorinated naphthalenes. The other monochloronaphthalene (2-), the ten theoretically possible dichloronaphthalenes, and the fourteen trichloronaphthalenes have all been prepared, generally from the corresponding amino-derivatives by diazotization and treatment with CuCl. They are of little industrial importance. 

Naphthalene-1-sulphonic acid crystallizes with 2HiO, m.p. 90 C. Used for the preparation of 1,8- and 1,5-nitronaphlhalene sulphonic acids. 

Naphthalene disulphonic acids are prepared by more prolonged sulphonation than in the preparation of the monosulphonic acids. Four isomeric acids are obtained. 

Naphthalene (risulphonic acids can be obtained by more drastic sulphonation of naphthalene or its mono- and disulphonic acids. Only the 1,3,5-, 1,3,6- and 1,3,7-acids are obtained. The most important of the iri-sulphonic acids is the 1,3,6-acid which is used for the preparation of H-acid, a dyestufT intermediate. 

Usually prepared on the large scale by caustic soda fusion of sodium naphthalene-1-sulphonate, but can also be obtained by high-temperature alkaline digestion of... 

Prepared commercially by NaOH fusion of sodium naphthalene-2-sulphonate. 

Prepared by the direct nitration of naphthalene with a mixture of nitric and sulphuric acids. Its chief use was for the preparation of l-naphthyiamine and its derivatives. 

Prepared by the oxidation of naphthalene with sulphuric acid at 270-300 C in the presence of HgSO under these conditions the... 

Schaffer s acid, CioHg04S. 2-hydroxy-7-naphthalene sulphonic acid. Obtained by sulphonating 2-naphthol with a small amount of sulphuric acid at a higher temperature than is used for the preparation of crocein acid. A valuable dyestuff intermediate. 

Picrates, Many aromatic hydrocarbons (and other classes of organic compounds) form molecular compounds with picric acid, for example, naphthalene picrate CioHg.CgH2(N02)30H. Some picrates, e.g., anthracene picrate, are so unstable as to be decomposed by many, particularly hydroxylic, solvents they therefore cannot be easily recrystaUised. Their preparation may be accomplished in such non-hydroxylic solvents as chloroform, benzene or ether. The picrates of hydrocarbons can be readily separated into their constituents by warming with dilute ammonia solution and filtering (if the hydrocarbon is a solid) through a moist filter paper. The filtrate contains the picric acid as the ammonium salt, and the hydrocarbon is left on the filter paper. 

The foUowing are typical experimental details for the preparation of naphthalene picrate. Dissolve 0 -1 g. of naphthalene and 0-2 g. of picric acid separately in the minimum volume of hot rectified spirit (about 2 ml.), mix the solutions and allow to cool. FUter and wash with 2 ml. of alcohol. RecrystaUise from hot alcohol, ethyl acetate or ether. 

Benzoquinone ( quinone ) is obtained as the end product of the oxidation of aniline by acid dichromate solution. Industrially, the crude product is reduced with sulphur dioxide to hydroquinone, and the latter is oxidised either with dichromate mixture or in very dilute sulphuric acid solution with sodium chlorate in the presence of a little vanadium pentoxide as catalyst. For the preparation in the laboratory, it is best to oxidise the inexpensive hydroquinone with chromic acid or with sodium chlorate in the presence of vanadium pent-oxide. Naphthalene may be converted into 1 4-naphthoquinone by oxidation with chromic acid. 

The commercial product, m.p. 53-55°, may be used. Alternatively the methyl -naphthyl ketone may be prepared from naphthalene as described in Section IV,136. The Friedel - Crafts reaction in nitrobenzene solution yields about 90 per cent, of the p-ketone and 10 per cent, of the a-ketone in carbon disulphide solution at — 15°, the proportions ore 65 per cent, of the a- and 35 per cent, of the p-isomer. With chlorobenzene ns the reaction medium, a high proportion of the a-ketone is also formed. Separation of the liquid a-isomer from the solid p-isomer in Such mixtures (which remain liquid at the ordinary temp>erature) is readily effected through the picrates the picrate of the liquid a-aceto compound is less soluble and the higher melting. 

The catalyst is prepared by the reaction of sodium metal with naphthalen( and results in the formation of a radical ion ... 

Bis(benZoxaZol-2-yl) Derivatives. Bis(benzoxazol-2-yl) derivatives (8) (Table 3) aie prepared in most cases by treatment of dicaiboxyhc acid derivatives of the central nucleus, eg, stilbene-4,4Cdicarboxyhc acid, naphthalene-l,4-dicarboxyhc acid, thiophene-2,5-dicarboxyhc acid, etc, with 2 moles of an appropriately substituted o-aminophenol, followed by a ring-closure reaction. These compounds are suitable for the brightening of plastics and synthetic fibers. 

Naphthalimides are prepared from naphthaUc anhydride obtained from naphthalene-1,8-dicarboxyhc acid, ie, the oxidation product of acenaphthene or its derivatives, by reaction with amines. They are utilized for synthetic fibers such as polyesters. 

Fluoronaphthalene [321-38-0] is prepared from 1-naphthylamine by the Balz-Schiemaim reaction in 52% yield or by diazotization in anhydrous hydrogen fluoride in 82% yield. Electrophilic substitution occurs at the 4-position, eg, nitration with fuming nitric acid in acetic acid gave 88% yield of l-fluoro-4-nitro-naphthalene [341 -92-4]. 

Eriedel-Crafts reaction of naphthalene or tetrahydronaphthalene derivatives with those of styrene or alkylbenzenes has been used in the preparation of high viscous fluids for traction drive (195). Similarly, Eriedel-Crafts reaction of tetraline and a-methylstyrene followed by catalytic hydrogenation provided l-(l-decalyl)-2-cyclohexyl propane, which is used as a highly heat resistant fluid (196). 

Isopropylnaphthalenes can be prepared readily by the catalytic alkylation of naphthalene with propjiene. 2-lsopropylnaphthalene [2027-17-0] is an important intermediate used in the manufacture of 2-naphthol (see Naphthalenederivatives). The alkylation of naphthalene with propjiene, preferably in an inert solvent at 40—100°C with an aluminum chloride, hydrogen fluoride, or boron trifluoride—phosphoric acid catalyst, gives 90—95% wt % 2-isopropylnaphthalene however, a considerable amount of polyalkylate also is produced. Preferably, the propylation of naphthalene is carried out in the vapor phase in a continuous manner, over a phosphoric acid on kieselguhr catalyst under pressure at ca 220—250°C. The alkylate, which is low in di- and polyisopropylnaphthalenes, then is isomerized by recycling over the same catalyst at 240°C or by using aluminum chloride catalyst at 80°C. After distillation, a product containing >90 wt % 2-isopropylnaphthalene is obtained (47). 

Mixtures containing various concentrations of mono-, di-, and polyisopropylnaphthalenes have been prepared by treating molten naphthalene with concentrated sulfuric acid and propjiene at 150—200°C followed by distillation (39). Products comprised of such isomeric mixtures have extremely low pour points, ie, ca —50° C, are excellent multipurpose solvents, and have been evaluated as possible Hquid-phase heat-transfer oils. 

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