STUDIES ON FUSED RING SYSTEMS II.A.REsOLUTION OF γ-(6-METHOXY-2-CARBOXY-1,2,3,4-TETRAHY-DRO-l-NAPHTHYL)-BUTYRIC ACID INTOd-AND 1-ISOMERS.B.PREPARATION OF METHYL d-AND l-1-HYDROXY-2-METHYL-2.CARBOMETHOXY-7-METHOXYI-l,2,3,4,9,10,11,12-OCTAHY-DRoPHE

γ-(6-Methoxy-2-carboxy-3,4-dihydro-l-naphthyl)-butyric acid was reduced in the presence of 5% Pd-C to the saturated acid, γ-(6-methoxy-2-carboxy-1, 2, 3, 4-tetrahydro- 1-naphthyl)-butyric acid, by the method of Bachmann and co-workers. From this reaction only one of the two diastereoisomers was obtained as the principal product. This acid was resolved into its optical antipodes with brucine in anhydrous methanol. The 1-γ-(6-methoxy-2-carboxy-1, 2, 3, 4-tetrahydro-1-naphthyl)-butyric acid-brucine salt, being less soluble, was readily obtained pure in crystalline form. After a middle fraction was taken off, the filtrate was evaporated to dryness and the d-γ-(6-methoxy-2-carboxy- 1, 2, 3, 4-tetrahydro-1-naphthyl)-butyric acid-brucine salt was obtained as a gummy mass. No attempt was made to purify this fraction of the salt. By dissolving the crystalline portion of the brucine salt in an appropriate amount of chloroform and shaking the solution with 2N KOH for four times, followed by acidification of the alkaline solution, pure 1-acid was obtained as a colorless crystalline compound. After recrystallization from benzene-ethanol, the pure 1-acid melted at 171-172°and its [α]_D~(25) is -123°. The d-acid was liberated from the last gummy fraction of the brucine salt in the same fashion and after recrystallization from benzene-ethanol, it melted at 171-172°and its [α]_D~(25) is +121°. The 1-acid was esterified with diazomethane and its dimethyl ester was cyclized by the Dieckmann reaction. The sodium salt of the product from the Dieckmann reaction was methylated with CH_3I following the method used by Bachmann and co-workers in their synthesis of estrone A, and a mixture of the diastereoisomers of d-1-keto-2-methyl-2- carbomethoxy-7-methoxy-1, 2, 3, 4, 9, 10, 11, 12-octahydrophenanthrene was obtained as a yellow oil. By recrystallizing from acetone-petroleum ether only the least soluble isomer was obtained pure. It melted at 114-116°and its [α]_D~(25) is +89°in anhydrous ethyl alcohol. In the same fashion, d-γ-(6-methoxy-2-carboxy-1, 2, 3, 4-tetrahydro-1-naphthyl)-butyric acid was esterified and cyclized by the Dieckmann reaction followed by methylation and a mixture of the diastereoisomers of 1-1-keto-2-methyl-2-carbomethoxy-7-methoxy-1, 2, 3, 4, 9, 10, 11, 12-octahydrophenanthrene was obtained as a yellow oil. By recrystallizing from acetone-petroleum ether, only the least soluble isomer was obtained pure. It melted at 114-116° and its [α]_D~(25) is -90.4°. By means of the Reformatsky reaction between d-1-keto-2-methyl-2-carbomethoxy-7- methoxy-1, 2, 3, 4, 9, 10, 11, 12-octahydrophenanthrene and methyl bromoacetate, a methyl- d-1-hydroxy-2-methyl-2-carbomethoxy-7-methoxy-1, 2, 3, 4, 9, 10, 11, 12-octahydrophenan- threne-1-acetate was obtained. This dimethyl ester was recrystallized from methyl alcohol. It melted at 86-88° with slight previous softening and its [α]_D~(25) is +113.6° in anhydrous ethyl alcohol. In the same way, the methyl 1-1-hydroxy-2-methyl-2-carbomethoxy-7- methoxy-1, 2, 3, 4, 9, 10, 11, 12-octahydrophenanthrene-1-acetate was obtained from the 1-keto ester. The dimethyl ester was recrystallized from methyl alcohol; it melted at 86-88° with previous softening and its [α]_D~(25) is -113° in anhydrous ethyl alcohol.