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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