Triethylamine → 2-[4-[4-(6-chloro-2-pyrazinyl)-1-piperazinyl]butyl]-3a,4,7,7a-tetrahydro-4,7-ethano-1,2-benzisothiazol-3(2H)-one 1,1-dioxide,hydrochloride

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Reaction Steps

A solution of 1.0 g (2.9 mmol) of 3a,4,7,7a-tetrahydro-2-(4-bromobutyl)-4,7-ethano-1,2-benzisothiazol-3(2H)-one 1,1-dioxide in 25 ml of anhydrous dimethylformamide is treated with 1.6 g (16 mmol) of triethylamine and 866 mg (3.2 mmol) of 1-(6-chloro-2-pyrazinyl)piperazine, monohydrochloride salt. The mixture is maintained at room temperature with stirring for 15 hours and then is partitioned between water and methylene chloride. The methylene chloride extracts are combined, dried over MgSO4, filtered and rotoevaporated to give crude free base. Preparative HPLC (silica gel; ethyl acetate: methylene chloride (9:1)) followed by evaporation of the appropriate fractions, treatment with ethanolic hydrochloric acid and recrystallization from methanol gives the title compound: mp. 263°-267° C.

Provenance & Evidence