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Chromic anhydride

By oxidation of the methyl derivative of an aromatic hydrocarbon with a solution of chromic anhydride in acetic anhydride and acetic acid. The aldehyde formed is immediately converted into the (/m-diacetate, which is stable to oxidation. The diacetate is collected and hydrolysed with sulphuric acid, for example ... [Pg.689]

Equip a I litre three-necked flask with a mechanical stirrer and a thermometer, and immerse the flask in a bath of ice and salt. Place 306 g. (283 ml.) of acetic anhydride, 300 g. (285 ml.) of glacial acetic acid and 25 g. of p-nitrotoluene in the flask, and add slowly, with stirring, 42 5 ml. of concentrated sulphuric acid. When the temperature has fallen to 5°, introduce 50 g. of A.R. chromic anhydride in small portions at such a rate that the temperature does not rise above 10° continue the stirring for 10 minutes after all the chromium trioxide has been added. Pour the contents of the flask into a 3 litre beaker two-thirds filled with crushed ice and almost fill the beaker with cold water. Filter the solid at the pump and wash it with cold water until the washings are colourless. Suspend the product in 250 ml. of cold 2 per cent, sodium carbonate solution and stir mechanically for 10-15 minutes filter (1), wash with cold water, and finally with 10 ml. of alcohol. Dry in a vacuum desiccator the yield of crude p-nitrobenzal diacetate is 26 g. (2),... [Pg.695]

Method 1. Cool a solution of 33 g. of hydroquinone in 150 ml. of 60 per cent, acetic acid contained in a 600 ml. beaker to below 5° in an ice bath. Dissolve 42 g. of chromic anhydride in 70 ml. of water, and add 30 ml. of glacial acetic acid. By means of a separatory funnel with bent stem and supported over the beaker, add the chromic anhydride solution... [Pg.745]

Chromium trioxide (chromic anhydride) [1333-82-0] M 100.0, m 197°, dec at 250° to Cr203, d 2.70 (pK 0.74, pK 6.49, for H2Cr04, chromic acid). Red crystals from water (0.5mL/g) between 100° and -5°, or from water/conc HNO3 (1 5). It separates when potassium or sodium dichromate are dissolved in cone H2SO4. Dried in a vacuum desiccator over NaOH pellets hygroscopic, powerful oxidant, can ignite with organic compounds. It is a skin and pulmonary IRRITANT. [Pg.413]

Cholestanone has been prepared by the oxidation of dihydro-eholesterol with chromic anhydride in acetic acid solution.1 The yield is sometimes diminished as a result of the partial acetylation of the sterol. [Pg.44]

The close relationship of eegonine to tropine is brought out by its Oxidation products, which when chromic anhydride in acetic acid is the agent used are tropinone, CgHijON (p. 74), tropinic acid, CgHi304N (P- 75) and ecgoninic acid, C HnOgN. The latter crystallises from benzene in colourless needles, m.p. 93°, and has been shown by Willstatter and Bode to W-methylpyrrolidone-2-acetic acid, and this was confirmed by Willstatter and Hollander s synthesis of the acid. [Pg.97]

ChromsMure, /. chromic acid, -anhydrid, n. chromic anhydride, chromium(VI) oxide, emisch, n. chromic acid mixture. -Ibsung. /. chromic acid solution, -salz, n. salt of chromic add, chromate. [Pg.93]

Aminomethyl-1-methyl-5-chloro-3(o-fluorophenyl)indole HCI Chromic anhydride Ammonia Hydrogen chloride... [Pg.657]

A solution of 60 g of chromic anhydride in 40 ml of water was added dropwise to a suspension of 60 g of 2-aminomethyl-1 -methyl-5-chloro-3-(o-fluorophenyl)-indole hydrochloride in 600 ml of acetic acid. The mixture was stirred at room temperature overnight. To the reaction mixture was added 1.1 liters of ether and 1 liter of water and then 800 ml of 28% ammonium hydroxide, in small portions. The ethereal layer separated, washed with water, dried, and concentrated under reduced pressure. The residue (51.8 g) was dissolved in 100 ml of ethanol, and 100 ml of 20% ethanollc hydrogen chloride was added to the solution and the mixture was cooled. The precipitate was collected by filtration to yield 46.5 g of 1 -methyl-7-chloro-5-(o-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepine-2-one hydrochloride, melt-... [Pg.657]

Methvl-5-nitro-3-phenvlindole-2-carbonitrile Hydrogen chloride Boron trifluoride etherate Chromic anhydride... [Pg.1083]

Q -Hydroxy-3Q (tetrahydropyran-2-yloxy)-2/3-(3Q -tetrahydropyran-2-yloxy-4-phenoxy-trans-1-buten-1 -yl)cyclopent-1Q -yl] -acetaldehyde a-hemiacetal Chromic anhydride Methanesulfonyl isocyanate Acetic acid... [Pg.1431]

Oxo-1 Id, 150i-bis-(tetrahydropyran-2-yloxy)-16-phenoxy-cis-5-trans-13-O -tetranorprosta-dienoic acid To a solution cooled to -10°C under nitrogen of 754 mg (1.3 mmols) 90 -hy-droxy-1 la.l 50 -bis-(tetrahydropyran-2-yloxy)-16-phenoxy-cis-5-trans-1 3-OJ-tetranorprosta-dienoic acid in 1 3 ml reagent grade acetone was added dropwise to 0.56 ml (1.41 mmols) of Jones reagent (chromic anhydride). After 20 minutes at -10°C, 0.260 ml 2-propanol was... [Pg.1431]

Cortisone acetate Demegestone Fluocortolone Medrogestone Norethindrone Chromic anhydride Fludiazepam HCI Nimetazepam Sulpro stone Cinchonidine Melphalan Cinnamoyl chloride Cinnarizine... [Pg.1624]

When a polymer is soaked in a heavily oxidative chemical liquid, such as chromic anhydride-tetrachloroeth-ane, chromic acid-acetic acid, and chromic acid-sulfuric acid, and treated under suitable conditions, polar groups are introduced on the polymer surface and the surface characteristics are improved [49,50]. The sur-... [Pg.823]

In a 500-cc. three-necked flask, fitted with a stirrer, thermometer, and dropping funnel, is placed 100 g. (1 mole) of chromic anhydride dissolved in 100 cc. of water, and 100 cc. of glacial acetic acid is added. The a-chlorohydrindene is then admitted through the funnel at such a rate as to keep the temperature at 35-40°, the flask being cooled externally. This addition takes about one and one-half hours, and after it is complete, stirring is... [Pg.47]

Like other 2,2-diaryltrichloroethanes, DFDT undergoes dehydrohalogenation in the presence of a base to yield l,l-dichloro-2,2-bis(p-fluorophenyl)-ethylene. The rate of this reaction has been found to be directly proportional to the temperature, and the rate constant for DFDT is approximately one seventh that for DDT at ordinary temperatures (18, 110). This ethylene derivative has been oxidized by the use of chromic anhydride to p,p -difluorobenzophenone, a sample of which did not depress the melting point of an authentic sample prepared by a different route (10). [Pg.162]

The method described above is a modification of a patented process,3 in which trinitrotoluene suspended in sulfuric acid is treated with chromic anhydride. [Pg.104]

Synonyms chromium trioxide chromic anhydride chromic acid ... [Pg.226]

Chromyl chloride is used in many organic synthetic reactions including oxidation and chlorination. It also is used as a catalyst in olefin polymerization in the preparation of chromium complexes and as a solvent for chromic anhydride. [Pg.229]

Synonym Gamma-Chloropropylene Oxide 3-Chloro-1,2-Propylene Oxide Chlorosulfonic Acid Chlorothene Chiorotoluene, Alpha Alpha-Chlorotoluene Omega-Chlorotoluene Chlorotrifluoroethylene Chlorotrimethylsilane Chlorsulfonic Acid Clilorylen Clip Chromic Acid Chromic Anhydride Chromic Oxide Chromium (VI) Dioxychloride Chromium Oxychloride Chromium Trioxide Chromyl Chloride Cianurina Citric Acid Citric Acid, Diammonium Salt Clarified Oil Clorox Cc Ral Coal Tar Oil Cobalt Acetate Cobalt Acetate Tetrahydrate Cobalt (II) Acetate Cobalt Chloride Cobalt (II) Chloride Cobaltous Acetate Cobaltous Chloride Cobaltous Chloride Dihydrate Cobaltous Chloride Hexahydrate Cobaltous Nitrate Cobaltous Nitrate Hexahydrate Cobaltous Sulfate Heptahydrate Cobalt Nitrate Cobalt (II) Nitrate Cobalt Sulfate Compound Name Epichlorohydrin Epichlorohydrin Chlorosulfonic Acid Trichloroethane Benzyl Chloride Benzyl Chloride Benzyl Chloride Trifluorochloroethylene Trimethylchlorosilane Chlorosulfonic Acid Trichloroethylene Cumene Hydroperoxide Chromic Anhydride Chromic Anhydride Chromic Anhydride Chromyl Chloride Chromyl Chloride Chromic Anhydride Chromyl Chloride Mercuric Cyanide Citric Acid Ammonium Citrate Oil Clarified Sodium Hypochlorite Coumaphos Oil Coal Tar Cobalt Acetate Cobalt Acetate Cobalt Acetate Cobalt Chloride Cobalt Chloride Cobalt Acetate Cobalt Chloride Cobalt Chloride Cobalt Chloride Cobalt Nitrate Cobalt Nitrate Cobalt Sulfate Cobalt Nitrate Cobalt Nitrate Cobalt Sulfate... [Pg.35]

CHROMIC ANHYDRIDE Chromic Oxide, Chromic Trioxide, Chromic Add Oxidizing Material, 1 (S) 3 (1 1 ... [Pg.98]


See other pages where Chromic anhydride is mentioned: [Pg.768]    [Pg.166]    [Pg.71]    [Pg.86]    [Pg.86]    [Pg.58]    [Pg.729]    [Pg.385]    [Pg.278]    [Pg.419]    [Pg.28]    [Pg.187]    [Pg.1083]    [Pg.754]    [Pg.953]    [Pg.368]    [Pg.100]    [Pg.316]    [Pg.768]    [Pg.792]    [Pg.792]    [Pg.792]    [Pg.186]    [Pg.278]    [Pg.326]   
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