Camphor sulfuric acid

Methyl methacrylate 4-Methylnitrobenzene 2- Methylpyridine Methylsodium Molybdenum trioxide Naphthalene 2-Naphthol Air, benzoyl peroxide Sulfuric acid, tetranitromethane Hydrogen peroxide, iron(II) sulfate, sulfuric acid 4-Chloronitrobenzene Chlorine trifluoride, interhalogens, metals Chromium trioxide, dinitrogen pentaoxide Antipyrine, camphor, phenol, iron(III) salts, menthol, oxidizing materials, permanganates, urethane... 

In a 3-1., three-necked, round-bottomed flask fitted with a powerful slow-speed stirrer having a Teflon blade, a 500-ml. dropping funnel, and a thermometer arranged to dip into the liquid is placed 588 g. (366 ml., 6 moles) of concentrated sulfuric acid. The flask is surrounded by an ice-salt mixture, the stirrer started, and 1216 g. (1170 ml., 12 moles) of acetic anhydride (Note 1) is added at such a rate that the temperature does not rise above 20° (Note 2). The separatory funnel is removed and 912 g. (6 moles) of coarsely powdered D,L-camphor is added (Note 3). The flask is then closed with a stopper and stirring is continued until the camphor is dissolved. The stirrer is replaced by a stopper, the ice bath allowed to melt, and the mixture left to stand for 36 hours (Note 4). The camphorsulfonic acid is collected on a suction filter and washed with ether (Note 5). After being dried in a vacuum desiccator at room temperature, the nearly white crystalline product weighs 530-580 g. (38-42%). It melts at 202-203° with rapid decomposition and is relatively pure (Note 6). 

Orange crystals camphor-like odor melts at 172.5°C vaporizes at 249°C sublimes above 100°C thermally stable above 500°C insoluble in water soluble in alcohol, ether and benzene also soluble in dilute nitric acid and concentrated sulfuric acid forming a deep red solution that fluoresces. 

Procedure Transfer about 300 mg of Camphorated Para-chlorophenol, accurately weighed, to a 200 ml pressure bottle containing 50 ml of freshly prepared dinitrophenyl-hydrazine TS. Close the pressure bottle, immerse it in a water bath, and maintain it at about 75° for k hours. Cool to room temperature, then transfer the contents to a beaker with the aid of 100 ml of dilute sulfuric acid (l in 12), and allow it to stand overnight. Collect the precipitate on a tared filter crucible, wash with 100 ml of dilute sulfuric acid (l in 12) and then with 75 ml of cold water, in divided portions, to remove the acid. Dry at 80° for 2 hours, cool and weigh. The weight of the precipitate so obtained, multiplied by O.U58I, represents the weight of C qH- O in the sample taken. 

Transfer about 0.2 g of d-camphor, accurately weighed, to a 300-ml glass stoppered flask, and dissolve in 25 ml of aldehyde-free ethanol. Add slowly 75 ml of 2,U-dinitrophenylhydrazine TS while shaking, and heat for U hours on a water bath under a reflux condenser. Cool, add 100 ml of diluted sulfuric acid (1 50), and allow to stand for 2h hours. Collect the precipitate so obtained on a glass filter (G3), wash the residue on the filter with cold water until the washings become neutral, dry for 2 hours at 105° and weigh as the 2,U-dinitrophenylhydrazone of d-camphor (C1gH2(-)N 0 332.36). ... 

Camphor can be determined colorimetrically with sulfuric acid and furfural (187)- To lcc of camphor solution, add 3 cc of ethanol (95%) and 10 drops of solution of furfural in 95% ethanol. Stir the mixture, add two drops of concentrated sulfuric acid and heat in a water bath. Then cool and add 5cc. of ethanol and compare the red to violet colour produced with a standard. The amount present can be determined within 10%. 

The colour reactions of camphor with aldehydes have been applied with p-dimethylaminobenzaldehyde in sulfuric acid (188). The yellow colour formed conforms to Beer s law and checks closely with the official NF method (15 ). The assay is carried out as follows ... 

Camphorquinone is extremely sensitive to oxidizing agents and yields camphoric acid when merely boiled in alkaline solution m the presence of air9 The diketone is boiled during one day with 3-4 molecular equivalents of alcoholic potassium hydroxide The alcohol is then evaporated off, and the residue taken up in water. After filtering, the camphoric acid is precipitated with dilute sulfuric acid and recrystallized... 

ACIDS, ORGANIC Acetyl sulfuric acid. d-(+)-Camphor-10-sulfonic acid. Formic acid. Methanesulfonic acid. Picric acid. p-Tolucnesulfonic acid. Trichloroacetic acid. Trifluoroacetic acid. Trifluorometh-ancsulfonic acid. 

For an excellent formal treatment of the Wagner-Meenvein rearrangements of camphor in sulfuric acid, which makes extensive use of C labeling, see O. R. Rodig and R. J. Sysko, J. Am. Chem. Soc., 94, 6475 (1972). 

Functionalization at C-9 (see Scheme 10) in camphor illustrates not only the complexity of the pathways when the possibility of Nametkin (2,3-methyl shift) and 2,6-hydride shifts are taken into account, but also one of the solutions to the simplification of the rearrangement.The product is a mixture of (-) )-and (-)-camphor-9-sulfonic acids, i.e. the pathway allows for racemization. Indeed camphor itself can be racemized in concentrated sulfuric acid by a similar pathway involving both Wagner-Meerwein and... 

Attacks some plastics, rubber, and coatings. Water solutions attack carbon steels at room temperature and stainless steels (especially if stabilized with sulfuric acid) above 176°F/80°C. Safety reminder When using HCN, it is xmwise to work alone. On small fires, use alcohol-resistant foam, dry chemical, or COj extinguishers. FORMOSA CAMPHOR (76-22-2) see camphor. 

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