Hydrochloric Acid → 1-(3,3-Diphenyipropyl)homopiperazine

Temperature

25 °C

A suspension of homopiperazine (2.9 g, 28.9 mmol) and homopiperazine dihydrochloride (5.0 g. 28.9 mmol) in EtOH was heated to 70° C. for 2 h, at which point a homogeneous solution of monohydrochloride salt (2.5 equiv) was obtained. The reaction mixture was treated with 3,3-diphenylpropyl methanesulfonate (6.7 g, 23.1 mmol, 1 equiv) and NaI (8.65 g, 57.7 mmol, 2.5 equiv) and heated to reflux for 16 h. The reaction mixture was cooled to 25° C. and the solvent was removed in vacuo. The crude product was partitioned between 2N aqueous NaOH (100 mL) and EtOAc (100 mL), and the aqueous layer was extracted with EtOAc (3×50 mL). The combined organic phase was washed with saturated aqueous NaCl (1×100 mL), dried (MgSO4) and concentrated. Chromatography (SiO2, 4×20 cm. 10% CH3OH— 5% Et3N-CH2Cl2) afforded the monoalkylated product (6.44 g, 6.79 g theoretical, 95%) as an amber oil.

1. customwas obtained
2. temperatureheated
3. temperatureto reflux for 16 h
4. customthe solvent was removed in vacuo
5. customThe crude product was partitioned between 2N aqueous NaOH (100 mL) and EtOAc (100 mL)
6. extractionthe aqueous layer was extracted with EtOAc (3×50 mL)
7. washThe combined organic phase was washed with saturated aqueous NaCl (1×100 mL)
8. dry with materialdried (MgSO4)
9. concentrationconcentrated
10. customChromatography (SiO2, 4×20 cm. 10% CH3OH— 5% Et3N-CH2Cl2) afforded the monoalkylated product (6.44 g, 6.79 g theoretical, 95%) as an amber oil

ORD record

ord-f1d25de1c1864f50a379dd85e7f898bf

Source dataset

uspto-grants-2004_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06686353B1