Benzophenone → HCID 23121897, compound

Participants

Reaction Conditions

Reaction Steps

1,1-Dimethylethyl 4-[(4-methylphenyl)methyl]-1-piperazine carboxylate (58 g, 0.2 mol) and N,N,N′,N′-tetramethylethylenediamine (35 g, 0.3 mol) were dissolved in tetrahydrofuran (400 mL), and the mixture was cooled to −78° C. under argon atmosphere. A 1.0 M solution of sec-butyllithium in hexane and cyclohexane (240 mL, 0.24 mol) was added dropwise over 1.5 hours, and the mixture was stirred at −78° C. for 3 hours. Then, the temperature was elevated to −30° C. for 2 hours. After cooling to −78° C. again, a solution of benzophenone (55 g, 0.3 mol) in tetrahydrofuran (200 mL) was added dropwise over 1 hour, and the resulting mixture was stirred overnight while elevating the temperature to room temperature. After ice cooling, an aqueous saturated ammonium chloride solution (300 mL) was added thereto, and the mixture was stirred for 30 minutes with ice cooling. Ethyl acetate (300 mL) was added thereto, and the process of phase separation was performed. The resulting organic layer was washed with water (500 mL) and dried over magnesium sulfate. The solvent was distilled off under reduced pressure, and to the residue was added diisopropyl ether-hexane (3:1, v/v, 300 mL). The obtained crystals were collected by filtration and washed with diisopropyl ether-hexane (3:1, v/v) to obtain the title compound (66 g, yield 82%).

Provenance & Evidence