Water-nitrogen-hexane-carbon dioxide

Carboxytellurophene2 Under nitrogen, a solution of 0.11 mol of 2-lithiotellurophene in a mixture of 150 ml of diethyl ether/60 ml of hexane is poured into a slurry of 300 g of dry ice in 400 ml of dry diethyl ether and excess carbon dioxide is allowed to sublime. 300 ml of water are then added, the mixture is shaken thoroughly, and the aqueous layer is separated and acidified with dilute sulfuric acid. The acidic solution is cooled to 5°, the yellow precipitate is filtered and recrystallized from ligroin using charcoal yield 9.3 g (38%) m.p. 111°. 

Canjar and Manning list values for thermodynamic functions of the following materials methane, ethane, propane, n-butane, n-pentane, isobutane, n-hexane, ethylene, propene, isobutene, acetylene, benzene, ammonia, carbon dioxide, carbon monoxide, hydrogen, nitrogen, oxygen, sulphur dioxide, and water. 

The typical natural gas constituents methane, ethane, propane, hutane, isohutane, pentane, isopentane, hexane, isohexane, heptane, octane, nonane, decane, undecane, dodecane, carbon dioxide, carhon monoxide, hydrogen, nitrogen, and water. 

To a solution of propynyl alcohol 48 (0.80 g, 2.7 mmol) in anhydrous dichloromethane (12 mL), under an atmosphere of nitrogen, was added octacarbonyldicobalt (1.02 g, 3.0 mmol) and the reaction was stirred at ambient temperature. The progress of the reaction was monitored by observing the evolution of carbon monoxide from the reaction mixture. TLC analysis, after fifteen minutes, showed the presence of a faster moving compound ( fO.45, 2 1 hexane diethyl ether). The reaction mixture was then cooled to -10 °C whereupon tetrafluoroboric acid diethyl ether complex (0.52 mL, 3.0 mmol, 85% by volume) was added and the mixture left to stir. TLC analysis, after five minutes, showed the presence of a new compound (R( 0.65, 2 1 hexane diethyl ether). To the reaction mixture, maintained at -10 °C, was added dropwise methanolic ceric ammonium nitrate (CAN, 6.67 g, 12.20 mmol, 30 mL) until the evolution of carbon dioxide ceased and the yellow color of CAN persisted (about fifteen minutes). TLC analysis of the reaction mixture revealed the presence of a new compound (/ f 0.40, 3 1 hexane diethyl ether). Residual methanol was removed in vacuo and the residue was partitioned between diethyl ether (25 mL) and water (25 mL). The aqueous phase was extracted with diethyl ether ( 3 x 20 mL) and the combined organic extracts were dried over anhydrous magnesium sulfate, filtered, and the solvent removed in vacuo to afford an oil. Purification was effected by column chromatography on silica (3 1 hexane diethyl ether) to afford the desired compound 49 (0.53 g, 66%) as a yellow oil. 

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