Potash alcoholic

The last example is an interesting application of the diene synthesis, for the adduct upon dehydrogenation (most simply by the action of oxygen upon its solution in alcoholic potash) yields 2 3-dimethylantbraquinone. 

Suitable organic solvents, such as ether, benzene, naphtha and the like, are more soluble than in water. This makes it possible to separate them from other substances which may accompany them in the water solution but which are not soluble in the solvents employed. Hence, one application of solvent extraction is the analytical determination of unsaponifiable oils and waxes in admixture with fatty material by submitting the mixture to vigorous saponification with alcoholic potash or, if necessary, sodium ethylate, and to dilute the product with water and extract with petroleum ether. The soaps remain in the aqueous solution while the unsaponifiable oils and waxes dissolved in the ether. The addition of a salt to an aqueous solution prior to extraction is sometimes practiced in some processes. In older processes, SOj is employed in the separation of aromatic and highly saturated hydrocarbons, taking advantage of the much greater solubility of the solubility of the aromatics and... 

Convolamine, Ci,H2304N. This alkaloid is hydrolysed by boiling alcoholic potash into tropine and veratric acid, and is, therefore, veratroyl-tropine. It has m.p. 114-5° and yields a picrate, m.p. 263-4° (dec.) aurichloride, m.p. 201-2° platinichloride, m.p. 216-7°, and methiodide, m.p. 273-5°. 

Dicentrine, CgoHjjOjN. (Items 36, 37, 39, 40 list, pp. 172-3.) This alkaloid crystallises, from ether, alcohol, or ethyl acetate in prisms, m.p. 168-9° [a]i) + 62-1° (CHCI3), and yields well-crystallised salts. It contains two methoxyl groups and yields a monoacetyl derivative, colourless leaflets, m.p. 202°, which is not hydrolysed even by boiling alcoholic potash. 1 The methiodide, B. CH3I. HjO, has m.p. 224°, and according to Manske, yields a methine base, m.p. 158-9°, the methiodide of which with potassium hydroxide solution decomposes into trimethylamine and a crystalline substance, presumably a substituted phenanthrenyl-ethylene, which polymerises on recrystallisation. 

Ergocominine formed from eigocornine on standing in aqueous alcoholic potash crystallises best from boiling alcohol (1 in 15) in massive prisms, m.p. 228° (dec.), and has -f- 409° or [a]f ° -f- 512° ic = 1 CHCI3). 

ISO Ajmaline was subsequently found to occur naturally in a specimen ol the drug collected in the Dun Valley (item 6, see above) along with a third isomeride, weoajmaline, m.p. 205-7°, which is convertible into iso-ajmaline by heating at 270° or by the action of alcoholic potash (Siddiqui ). 

Reaction.—a too c.c. flask to a short upright condenser (see Fig. 86) and to the upper end of the condensei attach a vertical delivery tube, dipping into an ammoniacal cuprous chloride solution. Pour 2—3 c.c. of ethylene bromide into the flask with 4 times its volume of strong methyl alcoholic potash, which is prepared by boiling methyl alcohol with excess of caustic potash on the water-bath with upright condenser. On gently heating, a rapid evolution of acetylene occurs and the characteristic brown copper compound (C2H,Cu,HjO) is precipitated from the cuprous chloride solution. 

Reactions.—i. Heat a few drops with double its volume of methyl alcoholic potash. On the addition of water a clear solution is obtained. Potassium formate and chloride are formed. CPICl3 + 4KOH = 3KC1+HC0.0K + 2H,0. 

Bring into a test-tube two drops of chloroform, one drop of aniline and i c.c. of alcoholic potash and warm zw the fume cupboard. Note the intolerable smell of phenyl carbamine (carbamine reaction), CHClj-bCQH3NHo-b3KOH=CQH5NC + 3KCI-t-3H.2O. Wash out the contents of the test-tube in the fume cupboaid. 

Quantitative Hydrolysis of Ethyl Benzoate -The quantitative estimation of an ester Ijy hycliolysis is conducted as follows a standaid half-normal solution of alcoholic potash is prepared by dissolving 7 grams of caustic potash m about an equal weight of water and diluting to 250 c.c. with absolute alcohol. The liquid is alloived to stand ovei night in a stoppered... 

A volume corresponding to about I gram is delivered into a round flask (200 c.c.) by attaching a piece of lubber tubing to the wide end of the apparatus and blowing until the liquid descends to the required graduation on the wide limb. Twenty-five c.c. of the standard alcoholic potash solution is added, and the mixture boiled on the water-bath wuth reflux condenser for twenty minutes. 

The esters are, for the most pait, colourless liquids or solids of low m. p., with a fruity smell and insoluble in water. They are hydrolysed by potash (most readily with alcoholic potash) and give amides with ammonia,... 

Nitroso-pinene is obtained from pinene-nitrosochloride by the action of alcoholic potash,... 

The identification of camphene is best carried out by its conversion into isobomeol under the influence of acetic acid in the presence of sulphuric acid. In order to effect this conversion, 100 grams of the fraction containing the terpene in substantial quantity are mixed with 250 grains of glacial acetic acid and 10 grams of 50 per cent, sulphuric acid. Tne mixture is heated for two to three hours on a water-bath to a temperature of 50° to 60°. At first the liquid separates into two layers, bat soon becomes homogeneous and takes on a pale red colour. Excess of water is added, and the oil which is precipitated, and which contains the isobomeol in the form of its acetate, is well washed with water repeatedly. It is then saponified by heating with alcoholic potash solution on a water-bath. The liquid is then evaporated and extracted with water, and the residue recrystallised from petroleum ether. 

When pinene hydrodide is heated with 40 per cent, alcoholic potash at 170° for four hours, a mixture of camphene and a second hydrocarbon is produced. This body, melts at 97 5° to 98° and has been... 

Both limonenes yield nitrosochlorides, Cj Hj NOCl, each of which can be separated into two modifications. There are thus four limonene nitrosochlorides they are known as the a- and /3- varieties of the dextro-and Zdew-rotatory forms of the terpenes. The a- and /3- forms, however, yield the same carvoxime on treatment with alcoholic potash. 

Here, as in every other case, the only difference between the derivatives of the two limonenes is that they are equally active optically in the opposite directions, and differ in the usual way in crystalline form. The nitrosochlorides, on boiling with alcoholic potash, yield nitroso-limonenes, CjdHjjNO. These are identical with the two carvoximes, and their constitution is probably Cj Hj. NOH. They both melt at 72° The carvoxime prepared from deicfro-limonene-nitrosochloride is faew-rotatory, whilst that from faew-limonene-nitrosochloride is dextro-rotatory. 

Hydrobrotnic acid converts dihydrocarvone into a hydrobromide, CioHjyOBr, which, when treated with cold alcoholic potash, readily loses hydrogen bromide. Instead, however, of the unsaturated substance, -dihydrocarvone, being regenerated as the result of this decomposition, a remarkable formation of a c /cZopropane ring takes place and carone is produced—... 

By treating this blue nitrosite, which Deussen calls )3-caryophyllene nitrosite, with alcoholic potash at 0°, it is converted to a colourless isomer, melting at 139°, which Deussen terms )3-caryophyllene isonitrosite. By treatment with boiling petroleum ether decomposition takes place and a compound melting at 159° is formed, of formula not yet established, and a nitro-compound of the formula Cj5H22N204, melting at 130 5°. 

---