Water → 1,3-Bis[4-(4-bromobenzoyl)-1-piperazinyl]propane

Temperatur

80 °C

To a suspension of 66.7 g (0.218 mmol) of the 1-(4-bromobenzoyl)piperazine hydrochloride prepared in Preparation Example 1 in dimethylformamide (223 mL) were added 11.3 mL (98% purity, 0.109 mmol) of 1,3-dibromopropane and 33.5 g (0.316 mmol) of sodium carbonate. The mixture was stirred for 6 hours at 80° C. Water (670 mL) was added to the reaction mixture with stirring at 80° C. and the mixture was stirred for 0.5 hour at the same temperature and for 1.5 hours at 20° C. The precipitates were collected by filtration and washed with water (3×45 mL) to obtain crude crystals. A suspension of the crude crystals in water-isopropanol (7:3, 570 mL) was stirred for 2 hours at 85° C., for 0.5 hour at room temperature, and for 1 hour at 0° C. Precipitated crystals were collected by filtration and washed with water-isopropanol (5:1, 2×110 mL), whereby 60.0 g of 1,3-bis[4-(4-bromobenzoyl)-1-piperazinyl]propane was obtained as colorless fine needles (yield 95%).mp: 170.0 to 173.0° C.

1. stirringwith stirring at 80° C.
2. stirringthe mixture was stirred for 0.5 hour at the same temperature and for 1.5 hours at 20° C
3. filtrationThe precipitates were collected by filtration
4. washwashed with water (3×45 mL)
5. customto obtain crude crystals
6. stirringwas stirred for 2 hours at 85° C., for 0.5 hour at room temperature
7. waitfor 1 hour at 0° C
8. customPrecipitated crystals
9. filtrationwere collected by filtration
10. washwashed with water-isopropanol (5:1, 2×110 mL)

ORD-Eintrag

ord-401c845db38743d9a76630930b7abad7

Quelldatensatz

uspto-grants-2004_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06787653B2