NOTES 2089 are m.p. 156", CY +81", X 240 mp ( e 17,080); and for 2b they are m.p. 194O, CY +27", 237 mp ( e 14,500). In this nonsensitized run no cholest-4,6-dien-3-one ( 5 ) was evident from the infrared or ultraviolet spectra of the fractions from chromatography.Photosensitized Oxygenation.-A solution of 1 (0.60 g.), hematoporphyrin (0.005 g.), and methylene blue (0.005 9.) in pyridine (70 ml.) was oxygenated and irradiated 42 hr. in the cold room as before. The crude product was an oil (0.55 9.) which gave a positive test for hydroperoxide and which had X 242 mp (e 5450). Its infrared spectrum (neat) showed strong peaks around 3330 and 1680 cm.-l (characteristic of OOH and a,fl-unsaturated ketone, respectively); a weak shoulder at 1725 cm.-1 and the absence of bands a t 952 and 795 cm.-l indicated that very little starting material remained. The product was reduced with sodium iodide in the normal way except acetic acid was omitted. After reduction the product had X 240 mp ( e 6100); this maximum was overshadowed by a new maximum that appeared at 285 mp when the ultraviolet solution was treated with a little hydrochloric acid or potassium hydroxide ( e 9300 and 9100, respectively). Separate runs showed that, when the acetic acid was not omitted in the sodium iodide treatment, the dienone chromaphore developed during the reduction. Based on the reported'' values for cholesta-4,6-dien-3-one ( 5 , X 284 mp, c 26,300)17 the acid or base treatment gave rise to ca. 35% of dienone 5 . A portion of the reduced material wa3 acetylated in the usual wayab to esterify secondary hydroxyl groups, and the product (0.123 g.) in benzene-hexane (1:3) was chromatographed on alumina (5 g.). Dienone 5 was formed on the column and was eluted with benzene-hexane (2:5) as a solid (0.032 9.) whose melting point (75-76') was undepressed by authentic 5 (m.p. 77-79')"; the infrared spectra were also identical.The remainder of the reduced product (0.370 g.) prior to acetylation was dissolved in benzene-hexane (1 : 1) and deposited on a column of alumina (13 g.), and elution with the same solvent was commenced after a 15-min. waiting period. Several solid and semisolid fractions (total 0.111 9.) were obtained whose individual infrared and ultraviolet spectra were essentially the same as that of dienone 5. Elution with benzene gave a hardened oil (0.030 9.) whose infrared spectrum was identical with that of authentic cholest-4-ene-3,6-dione, and whose ultraviolet spectrum showed X 253 mp ( e 9600). Benzene-ether (6:l) eluted several yellow solid fractions (total 0.065 g.) whose individual melting points fell between 145 and 174". Their ultraviolet spectra ( A 237-238 mp, e 11,200-12,000) and infrared spectra ( v 3450, 1680, 1270, 1230, 1190, 1035, 1015, 875 em.-') indicated that these fractions contained varying proportions of cholest-4-en-6p-ol-3-one (2b) and cholest-4-en-6a-ol-3-one (4b).Further elution of the column with ether gave brown, gummy material (0.050 9.) that seemed polymeric and was not investigated.Acknowledgment.-We are gra...

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Articles you may be interested inFar-infrared and combination-band spectra of the ring-puckering and ring-flapping vibrations of phthalan: A failure of the one-dimensional modelThe mid-infrared spectra (4000-250 em-I) of methylenecyclobutane, methylene-d2-cyclobutane-2,2-d2, and methylene-d 2 -cyclobutane-d6 have been examined closely for the occurrence of combination bands involving the ring-puckering vibration. A progression of sum bands for methylenecydobutane and a progression of difference bands for methylene-d2-cyclobutane-2, 2-d2 have been simultaneously fit by the onedimensional potential function in the ring-puckering coordinate x: V (x) = 4.229 X 10 5 x4 -1.694 X lO'x 2 • This potential function yields a barrier of 168±10 cm-1 at the planar conformation, in good agreement with the barrier of 160±40 cm-1 determined by other workers from the vibrational dependence of the rotational constants in the microwave spectrum. The detailed shape of the function does not agree as well and particularly the failure of the infrared function to account for the observed 0-1 splitting is noted. This had been noted earlier in the case of silacyclobutane and to a lesser degree, in the case of cyclopentene.

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Spiropentylamine has been synthesized with a deuterium label in the 4 position. Nitrous acid deamination has yielded 2-and 3-methylenecyclobutanols with deuterium distributed such as to suggest a mechanism involving initial ring enlargement or bicyclobutonium ion formation. Comparison is made with hydrolysis of spiropentyl chloride, which gives 2-hydroxymethyl-1,3-butadiene as the major product. Previouswork in this laboratory1 has shown that the nitrous acid deamination of spiropentylamine (1) gives mainly the methylene cyclobutanols, 2 and 3. 1 HXO,.