20-mesh zinc (preactivated by treating with concentrated aqueous hydrobromic acid) and 6.85 g. (8.64 mmol.) of «-III in 70 ml. of absolute ethanol was refluxed for 7 hr. (Remaining chunks of white solid were crushed after 50 min. of refluxing, and all «-III had dissolved in 90 min.; continued refluxing with zinc is probably responsible for the conversion of IV to bromine-free material and should therefore be avoided.) Isolated as described earlier in detail,3 the product, was distilled (short-path apparatus, at . µ) to give 2.55 g. of oil, b.p. (bath temperature) 80-110°; from analysis of another product prepared in the same way and thus indicated to be contaminated with about 6.5% of bromine-free material, the yield of crude «-IV is estimated to be about 88%. Assuming the bromine-free contaminant to be heptadecatriene (produced by zinc reduction of IV) and hence more volatile than the desired product, the crude -IV was freed of a small fraction, b.p. up to 116°( bath temperature) at 0.03µ, and the residue, predominantly all-08-8,11,14-1 a)-IV, ti2d 1.4885, d25 1.0134, analyzed and used in the preparation of -linolenic-l-C14 acid.
Diphenyldichlorosilane, phenylmethyldichlorosilane, phenylvinyldichlorosilane, phenyltrichlorosilane, p-chlorophenyltrichlorosilane, bis-p-chlorophenyldichlorosilane, bis-p-methoxyphenyldichlorosilane, and bis-p-ethylphenyldichlorosilane have been prepared by the reaction of arylmagnesium chlorides with appropriate silicon chlorides.
METALATION OF OLEFINS AND DiENES IN ALFIN POLYMERIZATION 3786potassium dodecanoate indicate that the transition occurs with the CS alcohol, but additional evidence, now being obtained, will be necessary before more definite ideas as to the extent of penetration of these long chain alcohols into the soap micelle can be advanced. SummaryAdditional evidence as to the presence of two loci of solubilization in soap micelles is obtained from solubilization data of hydrocarbon and polar compounds in soap solutions containing added electrolyte. The addition of potassium chloride to a 0.32 N potassium tetradecanoate (KCLO solution results in an enhancement of solubility of n-heptane and a decrease of n-octanol. With 0.05 N KC14-KC1 solutions, the solubilities of both polar and non-polar compounds increase. However, after the initial increase up to about 0.50 N potassium chloride, the solubility of the alcohol again decreases. Even though the critical micelle concentration of a soap depends only on the equivalent concentration of the ion opposite in charge to that of the colloidal electrolyte, the nature of both anion and cation affect solubilization. Thus in the solubilization of n-heptane for equivalent concentrations of additive, KC1 > K&OI > K4Fe(CN)6.3HpO whereas the reverse order holds when n-octanol is solubilized. However, these latter data present additional proof as to the two loci of solubilization, one in the bydrocarbon center of the micelle, the other in tbe palisade layer in the region occupied by the soap molecules. As the chain length of the solubilized alcohol is increased, there is a gradual transition from polar type to non-polar type solubilization most strikingly indicated when comparing Ca and CIO alcohols. Qualitative measurements of viscosity indicate that the addition of very small amounts of long chain alcohols to soap-salt systems result in the formation of very viscous, almost gel-like, systems. The maximum viscosities always QCCW a t concentrations of alcohol below the limit of solubilization (as indicated by turbidity).ST. PAUL, MINK.
separated and dissolved in ether. The ethereal solution was extracted with 10% aqueous potassium hydroxide until a portion of the extracts gave no precipitate when acidified.Is Treatment of the basic extract with Norite and then acidification with 10% hydrochloric acid gave a tan oil which solidified on standing. The isolated solid material was dried in a vacuum oven a t 50' and then weighed 33 g. (72%) and melted at 132-155'.Method B. A mixture of 9' g. (0.036 mole) of the tetrahydro-l,4naphthalenediacetic acid and 52 ml. of thionyl chloride was warmed carefully until the evolution of sulfur dioxide had ceased (15 min.). After removal of the excess thionyl chloride in vacuo, a solution of the residual acid chloride in 100 ml. of redistilled nitrobenzene was added with stirring over a period of 2 hr. to a cold (a') solution of 19 g. (0.145 mole) of anhydrous aluminum chloride in 300 ml. of nitrobenzene. After standing for 10-12 hr. in a refrigerator, the dark red complex was hydrolyzed with ice and 10% hydrochloric acid. The organic layer was washed with several portions of 15% hydrochloric acid and then with 5% potas sium hydroxide until a portion of the aqueous extract gave no precipitate when acidified. The basic solution was worked up as described in Method A to yield 5.1 g. (61%) of the crude keto acid, m.p. 132-156". Treatment of the solution of a portion in 10% aqueous alkali several times with Norite followed by isolation as before and recrystallization from ethanol yielded colorless crystals, m.p. 140-156". The wide range of melting point was attributed to the presence of more than one stereoisomer.Anal. Calcd. for CI4Hl4Od: C, 73.02; H, 6.50. Found: C, 72.75; H, 6.58.2~~3~4~6-Tetrahydro-6-acenaphtheneacetic acid (VIII). A modified Wolff-Kishner reduction of 7.1 g. (0.03 mole) of the keto acid with 35 ml. of 99% hydrazine hydrate, 28 ml. of ethanol, 35 ml. of diethylene glycol, and 3.3 g. of potassium hydroxide was carried out according to the pro-(18) A small amount of yellow, base insoluble material from the ether solution was isolated. It gave a positive reaction with 2,4dinitrophenylhydrazine but could not be identified as the diketone resulting from cyclization of both carboxyl side chains.cedure previously described3 except that the crude product was not chromatographed. The oil obtained solidified on standing to yield 6 g. (90%) of material which melted a t 89-96'. Recrystallization of a portion twice from petroleum ether afforded a product which melted at 99-10lo3 and apparently was predominantly the less soluble isomer. The ultraviolet and infrared absorption spectra of the recrystallized material were identical to those of a known sample. la,3,4,4a-Tetrahydro-l-pyracenone. Cyclization of 5.5 g. (0.025 mole) of the above tetrahydroacenaphtheneacetic acid by treatment with 50 g. of polyphosphoric acid16 was effected as described above for the preparation of 1-keto2aJ3,4,5-tetrahydro-5-acenaphtheneacetic acid (VII). The reddish brown solution obtained was poured into cold water and the mixture sti...
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