PURPOSE: To obtain buspirone having high purity in a high yield without producing by-products by hydrogenating a starting compd. by a novel method.
CONSTITUTION: A soln. of 8-[4-[4-(pyrimidin-2-yl)-piperazin-1-yl]-buty-2-yl]-8-aza- spiro [4,5-]decane-7,9-dione, represented by formula I, dissolved in a concn. of not less than 40 wt % in an inert org. solvent (pref. methanol or the like) is added to a suspension of a catalyst (pref. Pd supported on carbon) in an inert org. solvent (pref. THF or the like), and hydrogenation is carried out pref. at 20 to 30°C and 1 to 5 atm, followed by removal of the catalyst. 8-[4-[4-(Pyrimidin-2-yl)-piperazin-1-yl]-piperazin-1-yl]-butyl]-8-aza- spiro[4,5]decane-7,9-dione (i.e., buspirone) represented by formula II thus obtd. is then isolated. If necessary, the compd. is treated with hydrogen chloride in ethanol to give a hydrochloride of the compd.
GAABORU BURASUKOO
ZORUTAAN BUDAI
MARUGITSUTO CHIYOERUGOEE
EEBUA FURUJIYUGA
IMURE KUREBOBUITSUCHI
RAASUROO KONTSU
IRONA SUTORIYUHAARU
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