Partial Oxidation of an Aliphatic Side Chain

Preparation of Ruthenium Tetroxide (/5) In a 250-ml flask equipped with a magnetic stirrer and cooled in an ice-salt bath is placed a mixture of 0.4 g of ruthenium dioxide and 50 ml of carbon tetrachloride. A solution of 3.2 g of sodium metaperiodate in 50 ml of water is added and the mixture is stirred 1 hour at 0°. The black ruthenium dioxide gradually dissolves. The clear yellow carbon tetrachloride layer is separated and filtered through glass wool to remove insoluble materials. The solution may be used immediately or stored in the cold in the presence of 50 ml of sodium metaperiodate solution (1 g/50 ml). As prepared above, the solution is about 0.037 M in ruthenium tetroxide and contains 0.3 g/50 ml. 

n-BuTYL Butyrate from Di- -butyl Ether by Trichloroisocyanuric Acid (17) 

In a 200-ml round-bottom flask equipped with a magnetic stirrer and a thermometer is placed a mixture of 50 ml of di- -butyl ether and 25 ml of water. The flask is immersed in an ice bath and the mixture is cooled to 5°. In one portion is added 23.2 g (0.1 moles) of trichloroisocyanuric acid (Chapter 17, Section IV), and stirring in the ice bath is continued for 12 hours. The ice bath is removed and the mixture is stirred at room temperature for an additional 8 hours. The reaction mixture is then filtered to remove solids. The water is separated from the organic layer, which is then washed with two additional portions of water, dried with anhydrous sodium sulfate, filtered, and fractionated as above. 

A three-necked round-bottom flask is fitted with a dropping funnel, a thermometer, and a magnetic stirrer and is heated in a water bath to 30°. Tetralin (1.32 g, 0.01 mole) and 50 ml of 3.5 Anitric acid solution are placed in the flask and brought to temperature. Ceric ammonium nitrate (21.9 g, 0.04 mole) is dissolved in 100 ml of 3.5 N nitric acid, and the solution is added dropwise to the reaction mixture at a rate such that the temperature does not rise and only a pale yellow color is evident in the reaction mixture. At the completion of the reaction (1 to 2 hours), the mixture should be colorless. The solution is cooled to room temperature, diluted with an equal volume of water, and extracted twice with ether. The ether solution is dried with anhydrous sodium sulfate, filtered, and the ether is evaporated. The residue may be distilled to yield a-tetralone (bp 113-11676 mm or 170749 mm) or may be converted directly to the oxime, which is recrystallized from methanol, mp 88-89°. 

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