Benzaldehyde → Styryl[4-(4-fluorophenyl)piperazino] sulfone

Temperature

-78 °C

To a solution of LDA [8.5 mmol; prepared by slow addition of n-butyl lithium (3.5 ml, 8.5 mmol, 2.5 M in hexane) to a solution of diisopropylamine (860 mg, 8.5 mmol) in dry THF (5 ml) at −78° C.] at −78° C. was added a solution of 1-(4-fluorophenyl)-4-(methanesulfonyl)piperazine (1 g, 3.87 mmol) in THF (25 ml) dropwise. The mixture was stirred at −78° C. for 1 hour and a solution of diethylchlorophosphate (670 mg; 3.87 mmol) in THF (3 ml) was added. The mixture was stirred at −78° C. for 1 hour and benzaldehyde (450 mg; 4.24 mmol) in THF (3 ml) was added. The mixture was gently warmed to room temperature and stirred for 18 hours. The mixture was washed with aqueous ammonium chloride and extracted with ethyl acetate. The organic layers were washed with water, brine and dried over MgSO4. Purification of the residue on silica (eluant: dichloromethane) afforded 1-(4-fluorophenyl)-4(trans-β-styrenesulfonyl)piperazine as a white powder (621 mg, 46%).

1. stirringThe mixture was stirred at −78° C. for 1 hour
2. temperatureThe mixture was gently warmed to room temperature
3. stirringstirred for 18 hours
4. washThe mixture was washed with aqueous ammonium chloride
5. extractionextracted with ethyl acetate
6. washThe organic layers were washed with water, brine
7. dry with materialdried over MgSO4
8. customPurification of the residue on silica (eluant: dichloromethane)

ORD record

ord-e6e31bef8b7d4fe4949106e08c65badc

Source dataset

uspto-grants-2008_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07342020B2