Phosphorescence and the Triplet State
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چکیده
hours the rotation was again taken: [ C ~ ] ~ D +77.2 * 5" (a% +1.75 * 0.1'; 1 = 2 dm.). Treatment of 17-Isopregnan-3( a)-ol-20-one with Hydrogen chloride.-In a manner similar to the above a solution of 44.7 mg. of 17-isopregnan-3(a)-ol-20-one made up to 5 ml. with 4.3% methanolic hydrogen chloride was refluxed for four hours and then the rotation was taken: [ a I s 1 ~ $75.6 * 5" ( C Y ~ ~ D $1.35 * 0.1"; 1 = 2 dm.). Acetate of 17-bopregnan-3( ~~)-ol-2O-one.-A solution of 100 mg. of 17-isopregnan-3(a)-oI-20-one in 1 ml. of acetic anhydride and 0.66 ml. of acetic acid was refluxed for twenty minutes. After standing for three hours the solution was diluted to turbidity with water. The acetate separated in fine needles and was collected, weight 95 mg. After one recrystallization from methanol it melted a t 157-159' and mixed melting points with b:th the normal and 17-isopregnanolones gave about 30 depressions: [a]*'D -28.2 * 8' (24.16 mg. made up to 2 cc. with methanol; 1 = 1 dm.; a a 4 ~ -0.34 * 0.1'). Anal. Calcd. for CzzH380~: C, 76.61; H, 10.07. Found: C, 76.82; H, 10.32. Oxime of 17-Isopregnan-3(a)-oI-20-one.-A solution of 100 mg. of 17-isopregnan-3(a)-oI-20-one, 100 mg. of hydroxylammonium chloride, and 150 mg. of sodium acetate (trihydrate) in 2 ml. of methanol and 0.5 d. of water was refluxed for two hours. After cooling the solution was poured into water, extracted with ether, and the ether solution was dried over anhydrous sodium sulfate. The ether was removed and the residue was crystallized first from dilute acetone and then from methanol giving a white crystalline oxime melting at 192-197" (with decomposition). A mixed melting point with a sample of the oxime of the normal pregnan-3(~~)-01-20-one@ gave a depression of about 20". Anal. Calcd. for ColHssOzN: N, 4.20. Found: N, 4.57. Test with Digitonin.-To about 1 mg. of 17-isopregnan3(a)-ol-20-one in a few drops of 90% methanol was added an equal volume of a saturated solution of digitonin in 90% methanol. No precipitate was obtained even after standing for several hours.
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تاریخ انتشار 2001