Diisopropylethylamine → N-[4-{4-(1,2-benzisothiazol-3-yl)-1-piperazinyl}butyl]phthalimide

Participants

Reaction Conditions

Reaction Steps

An 18.01 g sample of 1-(1,2-benzisothiazol-3-yl)piperazine (83.7 mmol), 29.5 g of N-(4-bromobutyl)phthalimide (104.6 mmol) and 36 mL of N,N-diisopropylethylamine (375.4 mmol) were added to 400 mL of dry DMF. The solution was heated at 80° C. for 18 hours, and the solvent was then removed in vacuo. The residue was dissolved in 500 mL of methylene chloride and was washed with saturated aqueous sodium bicarbonate. The combined aqueous layers were re-extracted with 2 portions of methylene chloride. The combined organic layers were dried over Na2SO4, filtered, and concentrated in vacuo. The residue was crystallized from isopropanol with the addition of 4N HCl/isopropanol to give 23.03 g of the title compound as the hydrochloride, quarter hydrate, m.p. 253°-255° C.

Provenance & Evidence