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Author: Subject: Synthesis of Naphthalene Tetrachloride
TheNaKLaB
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[*] posted on 4-11-2011 at 17:37
Synthesis of Naphthalene Tetrachloride


Hey guys,

I'm planning on making Naphthalene Tetrachloride and reacting it with Nitric Acid to make Phthalic Acid. How could I possibly create this Naphthalene Tetrachloride?






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Neil
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[*] posted on 4-11-2011 at 18:01


You are going to get your self search engined slapped and your thread popped over to beginnings.

googling "naphthalene tetrachloride" gave this as the 6th result

http://books.google.ca/books?id=va0EAAAAYAAJ&pg=PA8&...

which says;

"We shall consider briefly the mode of preparation of each of the substances enumerated in the-above lists.

Bichloride of Naphthalene. 0erhardt's Chlorideoj'Naphthalene, C"H*C1*.— This, the first product of the action of chlorine* on naphthalene, may be prepared by passing chlorino over naphthalene until the product has passed through an oily stage and begins to become granular. The operation must not be carried so far as to chlorinate all the naphthalene. The mixture is to be heated in a dish for a long time to a temperature between 50° and 60°, then dissolved in ether and cooled to —10°, and the ethereal solution mixed with alcohol and oil exposed to the air until two-fifths of the oil have been deposited: this oil contains the oily chloride of naphthalene. The third fifth may also bo collected; it is the solid chloride, C'°HBC1*, in a state of purity.

Bichloride of naphthalene is oily, soluble in all proportions in ether, but less soluble in alcohol. On distillation it decomposes slowly, giving off hydrochloric acid, and yielding chloronaphthaleue, C'°H'C1. With alcoholic potash it yields the lastnamed substance and chloride of potassium.

Bichloride-of Bromonaphthalene. C'H'Br.Cl2. Laurent's Subckloride of Bronaphtase. When chlorine is passed into crude bromonaphthalene, it thickens and deposits a crystalline matter. Ether is poured on the product, and the mixture is allowed to remain fur 2-t hours. The oily portion is to bo decanted, and the crystalline powder washed with ether and then dissolved in a large quantity of boiling ether. By spontaneous evaporation the chloride of bromonapthalene is deposited in small rhomboidal tables resembling those of dichloride of naphthalene. The crystals are derived from an oblique prism with a rhombic base (Gerhardt, loc. cit.). Melts at 165°.

Bibromide of Tribromonaphthalenc. C'°HsBr3.Br2. Subltromidc of Bronaphtise. Produced, together with dibromide of dibromonapthalene when dibromonaphthalene is treated with bromine. On boiling the mixture with ether, the dibromide of tribromonaphthalene dissolves, and on spontaneous evaporation is deposited as a tlocculent powder consisting of white microscopic needles. It decomposes on distillation, giving off hydrobromic acid, a little bromine, and a crystalline matter very slightly soluble in ether.

Tetrachloride of Naphthalene. Gerhardt's Bichloride of naphthalene. C,0HS.C1'. Hydrochlorate of chloronaphlalese.—This substance exists in two isomeric modifications.

Modification a.—When a rapid current of chlorine is passed over naphthalene in rather large quantity (say one or two pounds) the naphthalene fuses, hydrochloric acid is disengaged, and, if the current be sustained, the whole, after some time, begins to thicken again. The mixture at this point contains oily dichloride of naphthalene, tetrachloride of naphthalene a, the modification /3, and tetrachloride of chloronaphthalene, the last two in small quantity. Ether is to be poured on the mixture to render it more fluid. After repose for some hours the oily portion is to be decanted and the residue thrown on a filter. After being well drained the residue is dissolved in benzene and allowed to cool very slowly. The tetrachloride soon begins to crystallise out, and if the solution be tolerably large in quantity (half a gallon or a gallon) fine rhombohedrons will be deposited. The writer has sometimes obtained them nearly a quarter of an inch on the side. They are colourless, transparent and exactly resemble calc-spar. They also possess powerfully-the property of double refraction.

This modification of tetrachloride of naphthalene is inodorous, insoluble in water, slightly soluble in alcohol, moderately so in ether, hut very soluble in benzene, rock-oil and analogous liquids. It melts at 160° and solidifies to a crystalline mass on cooling. If a crystal be added to the partially fused chloride, the whole will solidify at about 150° in rhombic tablets. On the other hand, if the chloride be perfectly fused and allowed to cool without addition, the mass sometimes solidifies at 150° in rhombic tallies, and sometimes between 100° and 110° in concentric needles.

It is decomposed by distillation, giving off hydrochloric acid and an oily matter. Only a trace of carbon (1 or 2 per cent.), remains in tho retort The distillate consists of a mixture of four isomeric forms of dichloronaphthalene. These products are always accompanied by a small quantity of undecomposed tetrachloride of naphthalene. Alcoholic potash converts it into the two modifications e and ad of dichloronaphthalene.

Modification 0.—This variety of tetrachloride of naphthalene is distinguished from a by its solubility in ether. It is formed, as already observed, at the same time as the modification o when chlorine is passed over naphthalene. It is contained iu the oily portion rendered more fluid by ether which has been directed to be poured off from the solid portion which consists chiefly of o. The liquid containing ether is to be cooled to 03 and kept at that temperature for 48 hours ; it will then solidify to a mass resembling frozen olive oil. The solid portion may be collected on linen and freed from the mother-liquid by pressure. The solid is to be dissolved in ether containing about one-tenth of alcohol. The solution left to spontaneous evaporation yields a crystalline mass containing both the modifications. The mass must be well pressed, dissolved in boiling alcohol, and very slowly cooled. The first crystals which form will be almost puro a, the rest of the crops will be successively richer in /3. By repeated crystallisations from ether the latter may be obtained pure. Its purity may be known by its dissolving rapidly and without residue in ether.—It is colourless, inodorous, very soluble in ether, alcohol, benzene, and similar hydrocarbons. It crystallises in small lamellie of indeterminable form which unite into globes often of considerable diameter. Submitted to distillation it gives on? hydrochloric acid, an oil, and the modification c of dichloronaphthalene. Boiled with alcoholic potash it yields an oil and the modification f of dichloronaphthalene."

Which is as good a research starting point as any.






[Edited on 5-11-2011 by Neil]

[Edited on 5-11-2011 by Neil]
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Nicodem
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5-11-2011 at 10:05

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