Pyrogallol dimethyl ether is found in beechwood tar.
Meta-aminophenol is prepared by reducing metanitrophenol, or by heating resorcin with ammonium chloride and ammonia to 200° C. Dimethyl-meta-aminophenol is prepared by heating meta-aminophenol with methyl alcohol and hydrochloric acid in an autoclave; by sulphonation of dimethylaniline, the sulphonic acid formed being finally fused with potash; or by nitrating dimethylaniline, in the presence of sulphuric acid at 0° C. In the latter case a mixture of nitro-compounds is obtained which can be separated by the addition of sodium carbonate.
Dimethyl-meta-aminophenol crystallizes in small prisms which melt at 87° C. It condenses with phthalic anhydride to form rhodamine, and with succinic anhydride to rhodamine S.
Its tetramethyl-diamino derivative, which is formed by condensing formaldehyde with dimethyl-meta-aminophenol and subsequent elimination of water from the resulting diphenyl methane derivative, is the leuco base of pyronine, into which it passes by oxidation.
Aniline, C 6 H 5 NH 2, monomethyl aniline, C 6 H 5 NH CH 3, and dimethyl aniline, C 6 H 5 N(CH 3) 2, are in increasing order of basicity.
Bamberger opposed Claus' formula on the following grounds: - The molecule of naphthalene is symmetrical, since 2.7 dioxynaphthalene is readily esterified by methyl iodide and sulphuric acid to a dimethyl ether; and no more than two mono-substitution derivatives are known.
Reduction of this ester leads to the formation of ammonia, hydroxylamine, and dimethyl pyrrol dicarboxylic ester, C(CH3): C C02R HN< C(CO 2 R) :C CH3.
An important oxidation synthesis of aromatic acids is from hydrocarbons with aliphatic side chains; thus toluene, or methylbenzene, yields benzoic acid, the xylenes, or dimethyl-benzene, yield methyl-benzoic acids and phthalic acids.
It will be advantageous if the spectra of ammonia, benzene, aniline and dimethyl aniline be compared, when the re-' markable coincidences will at once become apparent, as also the different weighting of the molecule.
For dimethyl ketone or acetone, see Acetone.
It is a liquid of boiling point 136° C. It condenses readily with aniline to give ay-dimethyl quinoline.
Dimethyl sulphate, (CH3)2S04, is a colourless liquid which boils at 187 °-188° C., with partial decomposition.
Great care should be taken in using dimethyl and diethyl sulphates, as the respiratory organs are affected by the vapours, leading to severe attacks of pneumonia.
Its hydrochloride melts at 163° C., and crystallizes from alcohol in colourless deliquescent prisms. Acetic anhydride converts the base into an acetamino-dimethyl pyrimidine, acetic acid and acetamide being also formed.
For example, aa-dimethyl urea is sweet, aß-dimethyl urea is tasteless; p-phenetol carbamide or dulcin, NH 2 CO NH C 6 H 4.0C 2 H 51 is sweet, while the di-p-phenetol carbamide, CO(NH C 6 H 4.0C 2 H 5) 21 is tasteless.
Hydrochloric acid at 200° C. decomposes into oxalic acid, carbon dioxide and methylamine, whilst an alcoholic solution of a caustic alkali gives dimethyl urea and oxalic acid.
It is prepared by the action of carbonyl chloride on dimethyl aniline in the presence of aluminium chloride: COC12+2C6H5N(CH3)2=2HC1+CO[C6H4N(CH3)2]2.
ACETONE, or DIMETHYL KETONE', CH3.CO.CH3, in chemistry, the simplest representative of the aliphatic ketones.
The dimethyl ether or veratrol is also used in medicine.
XYLENE, or Dimethyl Benzene, C6H4(CH3)2.
It combines directly with methyl iodide to form dimethyl coninium iodide, C10H22NI, which by the destructive methylation process of A.
Isothujone, C10H160, is dimethyl-I.
A dimethyl ether of inactive inosite is dambonite which occurs in caoutchouc from Gabon.
The dimethyl arsine (or cacodyl) compounds have been most studied.
Monomethyl and dimethyl aniline are colourless liquids prepared by heating aniline, aniline hydrochloride and methyl alcohol in an autoclave at 220°.
Monomethyl aniline boils at 193-195'; dimethyl aniline at 192°.