Thionyl Chloride → HCID 85835212, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of bis(3-(trifluoromethyl)phenyl)methanol (1.1 g, 3.4 mmol) in CH2Cl2 (10 mL) was added dropwise thionyl chloride (0.50 ml, 6.9 mmol) at rt. The reaction was stirred at 50° C. for 4 h, concentrated under vacuum, azeotroped with toluene, and dried under vacuum to give crude chlorobis(3-(trifluoromethyl)phenyl)methane. The crude chlorobis(3-(trifluoromethyl)-phenyl)methane was added to a solution of piperazine (0.81 ml, 10 mmol) in acetonitrile (10 mL), heated to 100° C. for 18 h and concentrated under vacuum. The residue was dissolved in CH2Cl2 (150 mL) and washed with 1N NaOH (150 mL). The organic layer was dried with K2CO3, filtered, and concentrated to give 1-(bis(3-(trifluoromethyl)-phenyl)methyl)piperazine. The crude 1-(bis(3-(trifluoromethyl)phenyl)-methyl)piperazine was dissolved in acetonitrile (10 mL) and tert-butyl bromoacetate (0.55 mL, 3.4 mmol) and triethylamine (0.96 ml, 6.9 mmol) was added. The solution was stirred for 4 h, diluted with water, and extracted with CH2Cl2. The organic layer was washed with saturated NaCl solution, then dried over Na2SO4, and concentrated. The crude product was purified by ISCO using 0-50% EtOAc in hexanes to give tert-butyl 2-(4-(bis(3-(trifluoromethyl)-phenyl)methyl)piperazin-1-yl)acetate (0.86 g, 50% yield). MS (ESI, pos. ion) m/z: 503.1 (M+1), which was then converted to the title compound by proceeding as described in Example 4 above.

Provenance & Evidence