1-(2-Chloroethyl)-4-fluorobenzene → 4-(4-Fluorophenethyl)piperazin-2-one

Temperature

85 °C

Piperazinone (1.20 g, 12.1 mmol), 1-fluoro-4-(2-chloroethyl)benzene (2.45 g, 12.1 mmol) and i-Pr2NEt (3.25 g, 4.5 ml, 25 mmol) were combined in acetonitrile (25 mL) and heated to 85° C. for 2 h. The mixture was concentrated and 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 (1.30 g, 48%) as a white solid: 1H NMR (300 MHz, CDCl3) δ 7.18-7.13 (m, 2H), 7.00-6.94 (m, 2H), 6.45 (s, 1H), 3.39-3.35 (m, 2H), 3.20 (s, 2H), 2.78-2.62 (m, 6H).

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

ORD record

ord-bba2b78b4c1a4776ad2387814f4a3c9f

Source dataset

uspto-grants-2014_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08697700B2