Hydrochloric Acid → 1-[3-(4-tert-Butylphenyl)-2-methylpropyl]-3,5-dimethylpiperidine

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Reaction Conditions

Reaction Steps

67.8 g of 3-(p-tert.butyl-phenyl)-2-methyl-propionaldehyde and 50 g of 3,5-dimethyl-piperidine are heated at reflux in 50 ml of toluene in a water-separator under nitrogen gasification until the water-cleavage has been completed (16 hours). Subsequently, there are added dropwise at room temperature while stirring 16.8 g of formic acid, the temperature rising to 36°-40° C. The mixture is then heated to 80° C. for 1 hour. 165 ml of 2-N hydrochloric acid are added to the cooled solution, the toluene solution is separated, the aqueous-hydrochloric acid solution is made alkaline with 66 ml of 6-N sodium hydroxide and the product is extracted with ether. The combined ether extracts are washed with water, dried over sodium sulphate and evaporated. By distillation there is obtained pure 1-[3-(p-tert.butyl-phenyl)-2-methyl-propyl]-3,5-dimethyl-piperidine of boiling point 113°-114° C./0.09 Torr.

Provenance & Evidence