Über ein Bestrahlungsprodukt des Δ_6,8‐Cholesta‐dienols

Valence bond isomers of aromatic systems. Bicyclo[2.2.0]hexa-2,5-dienes (Dewar benzenes)

“…Diimide (generated by decarboxylation of azodicarboxylic acid in the manner previously described36) hydrogenation of hydrocarbon 4 in pyridine-water-acetic acid solution was carried out. The product was identified as bicyclo[2.2.0]hexane (41), by comparison with an authentic sample37a,b as well as by pyrolysis to biallyl, known to be formed when bicyclo[2.2.0] is heated.37a 41 By means of preparative vpc methods, there was obtained a small amount of solvent-free, reasonably pure Dewar benzene, which was dissolved in carbon disulfide or tetrachloride, the resulting solution being used for measurement of the infrared spectrum (Figure 2). Notably different from the ir spectrum of benzene, the spectrum of Dewar benzene featured intense bands at 705 and 785 cm-1, and a medium band at 825 cm-1, ascribable to C-H out-of-plane deformations.…”

ISOLATION AND SYNTHESIS OF A NEW STEROL FROM RAT FECES1,2

“…(8) (a) E. Wenkert and L. H. Liu, Expcrientia, 11, 3(12 (1955); (b) E. Wenkert and D. K. Roychaudhuri, in press. (9) Cf. H. Schwarz and E. Schlittler, Ilelv.…”

The Anthrasteroid Rearrangement. I. The Formation and Proof of Structure of Anthraergostapentaene1

“…20,000) for ergosteryl-acetate. The mother liquor was chromatographed on alumina, but only traces of material were eluted by 5 and 10% benzene in petroleum ether which should have removed a hydrocarbon. An additional amount of the B-isomers was eluted by benzene.…”