[O-2:1].[O-2:2].[O-2:3].[Cr+6:4].S(=O)(=O)(O)[OH:6].[CH:10]1([C:16]#[C:17][CH2:18]O)[CH2:15][CH2:14][CH2:13][CH2:12][CH2:11]1>O.CC(C)=O>[Cr:4]([OH:6])([OH:3])(=[O:2])=[O:1].[CH:10]1([C:16](=[O:1])[C:17]#[CH:18])[CH2:15][CH2:14][CH2:13][CH2:12][CH2:11]1A solution of chromic acid was prepared by dissolving 106.88 g chromium trioxide in 400 ml water and then adding 92 ml concentrated sulfuric acid. This solution was added in dropwise fashion over a 3 hr. period to an ice cooled, stirred solution of 120 g 3 cyclohexyl-1-propyn-3-ol, prepared as shown in Preparation 1, in 175 ml acetone. The resulting mixture was diluted with 500 ml water and the product was extracted into 1 liter of diethyl ether. The ether extract was washed with 250 ml saturated sodium bisulfite solution and was dried over sodium sulfate. The diethyl ether was removed by distillation under nitrogen atmosphere and the resulting residue was purified by Kugelrohr distillation (65° C., 0.1 mm Hg) to give 84.9 g of 3-cyclohexylprop-1-yn-3-one as an oil: MS m/z=136 (M+) Calcd. for C9H12O: C, 79.37; H, 8.88. Found: C, 79.24; H, 8 60.
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