Dimethyl Sulfoxide → 4-(5-(4-(3-Cyanopropyl)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3,4]octan-7-yl)-2-(trifluoromethyl)benzonitrile

Participants

Reaction Steps

A solution of DMSO (0.01 mL, 0.12 mmol) in dry dichloromethane (1 mL) was added to a stirred solution of oxalyl chloride (0.01 mL, 0.09 mmol) in dry dichloromethane (2 mL) at −78° C. After 15 min, a dichloromethane solution of 4-(4-(7-(4-Cyano-3-(trifluoromethyl)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)phenyl)butanamide, RD130 (Formula 52) (35 mg, 0.07 mmol) was added to the reaction mixture. Stirring was continued for 20 min at −78° C., and then biethylamine (0.03 mL, 0.22 mmol) was added. After 30 min at −78° C., the reaction mixture was warmed to room temperature and then reaction was quenched with saturated aq. NH4Cl solution. The reaction mixture was diluted with dichloromethane, and extracted with dichloromethane. The organic layer was dried over MgSO4, concentrated and chromatographed (dichloromethane:acetone, 95:5) to yield 4-(5-(4-(3-Cyanopropyl)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-7-yl)-2-(trifluoromethyl)benzonitrile, RD170 (Formula 53) (29 mg, 87%) as a viscous oil. 1H NMR δ 7.98 (d, 1H, J=1.8 Hz), 7.98 (d, 1H, J=8.3 Hz), 7.86 (dd, 1H, J=8.3, 1.8 Hz), 7.43 (d, 2H, J=8.4 Hz), 7.27 (d, 2H, J=8.4 Hz), 2.90 (t, 2H, J=7.3 Hz), 2.63-2.73 (m, 2H), 2.52-2.62 (m, 2H), 2.42 (t, 2H, J=7.3 Hz), 2.18-2.30 (m, 1H), 2.07 (p, 2H, J=7.3 Hz), 1.63-1.73 (m, 1H).

Provenance & Evidence