Potassium Carbonate → 4-(4-Chlorophenethyl)piperazin-2-one

Temperature

85 °C

Piperazinone (1.04 g, 10.4 mmol), 1-chloro-4-(2-chloroethyl)benzene (2.28 g, 10.4 mmol) and K2CO3 (1.72 g, 12.4 mmol) were combined in DMSO (12 mL) and heated to 85° C. for 2 h. The mixture was partitioned between H2O (20 mL) and CH2Cl2 (20 mL), and the organic layer was removed. The aqueous layer was extracted with CH2Cl2 (3×20 mL), the combined organics were concentrated, and the residue was dissolved in 2 N HCl (50 mL). This acidic mixture was washed with CH2Cl2 (3×20 mL) and then made basic with 6 N NaOH. The basic mixture was extracted with CH2Cl2 (3×20 mL), and the extracts were combined, dried and concentrated to provide the title compound (1.51 g, 60%) as an orange solid: 1H NMR (500 MHz, DMSO-d6) δ 7.72 (s, 1H), 7.32 (d, J=8.8 Hz, 2H), 7.26 (d, J=8.8 Hz, 2H), 3.14-3.10 (m, 2H), 2.96 (s, 2H), 2.74 (t, J=6.6 Hz, 2H), 2.62-2.53 (m, 4H).

1. customThe mixture was partitioned between H2O (20 mL) and CH2Cl2 (20 mL)
2. customthe organic layer was removed
3. extractionThe aqueous layer was extracted with CH2Cl2 (3×20 mL)
4. concentrationthe combined organics were concentrated
5. dissolutionthe residue was dissolved in 2 N HCl (50 mL)
6. washThis acidic mixture was washed with CH2Cl2 (3×20 mL)
7. extractionThe basic mixture was extracted with CH2Cl2 (3×20 mL)
8. customdried
9. concentrationconcentrated

ORD record

ord-1409eeefd6484febba3bd6ded0ce3ee5

Source dataset

uspto-grants-2014_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08637501B2