Benzaldehyde → 2-Cyclohexyl-1-(pyridin-2-YL)ethanamine

Beteiligte Stoffe

Reaktionsschritte

To 465 g (4.3 moles) of 2-(aminomethyl) pyridine was added with stirring 456 g (4.3 moles) of benzaldehyde. The temperature was increased to 70°-80° C. The mixture was diluted with 2 L of MTBE and the water was removed by stirring the solution with 200 g of sodium sulfate overnight. The mixture was filtered and washed with 2 L of MTBE. To remove the remaining water, 100 g of molecular sieves were added. To the mixture was added 483 g (4.3 moles) potassium t-butoxide in portions followed by 842 g (4.38 moles) of cyclohexylmethyl methanesulfonate. After 10-20 hours, the mixture was hydrolyzed by the addition of 5 L water containing 720 mL of hydrochloric acid. The organic phase was separated and discarded. The aqueous phase was washed with 0.5 L of methylene chloride and basified with 0.5 L of ammonium hydroxide. The product was extracted with petroleum ether to yield 452 g of crude mine. The amine was purified by vacuum distillation at 88° C. and 0.5 Torr to give 353 g (35%) of 1-(R,S)-(2-pyridyl)-2-cyclohexylethylamine.

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