Potassium Carbonate → Tert-butyl 3-hydroxy-4-{4-[3-(2-methoxybenzyloxy) propoxy]phenyl}piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

(α) A solution of 5.2 g (17.7 mmol) of tert-butyl (3RS,4RS)-3-hydroxy-4-(4-hydroxy-phenyl)-piperidine-1-carboxylate [Example 46 (b)] and 3.37 ml (3.8 g, 17.7 mmol) of 2-methoxybenzyl 3-chloropropyl ether in 18 ml of absolute DMF was treated with 3.7 g (26.9 mmol) of anhydrous potassium carbonate and stirred at 120° C. for 60 h. For the working-up, the reaction mixture was partitioned between 250 ml of water and 250 ml of ethyl acetate. The organic phase was separated and the aqueous phase was extracted three times with 100 ml of ethyl acetate each time. The combined organic phases were washed twice with 100 ml of water each time and finally the solvent was distilled off under reduced pressure. The crude product was crystallized by treatment with ether. There were obtained 7.3 g (88% of theory) of tert-butyl (3RS,4RS)-3-hydroxy-4-[4-[3-(2-methoxy-benzyloxy)-propoxy]-phenyl]-piperidine-1-carboxylate as a colourless solid; MS: 472 (M+H)+.

Provenance & Evidence