Iodine → 4-Chloro-6-methyl-2-(4-methylphenyl)quinoline

Beteiligte Stoffe

Reaktionsschritte

To a solution of 4.3 g (25 mmol) of p-bromotoluene in 50 ml of ether cooled to 5° was dropwise added 15 ml of a 1.6M solution of butyl lithium in hexane, while maintaining the temperature below 5°. This mixture was stirred at 5° for 10 min and at 30° for 10 min. and then cooled to -20°. A solution of 4.0 g (22 mmol) of 4-chloro-6-methylquinoline, prepared as in Example 25, in 20 ml of ether was added while maintaining the temperature at -20°. It was then allowed to stir at room temperature for 15 min. To the reaction mixture was then added 10 ml of water and 5 g of iodine, and 60 ml of 3N sodium hydroxide. After 20 min of stirring the organic layer was separated. The aqueous phase was extracted with an equal volume of ether. The organic phases were combined, washed with water, dried over sodium sulfate, and concentrated in vacuo to leave the above-named 4-chloroquinoline as a yellow oil. A solution of this oil in methylene chloride was filtered through a plug of alumina. The filtrate was concentrated in vacuo to give 3.22 g of the above-named product, mp 40°-50°.

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