Hydrochloric Acid → 4-(7-(6-cyano-5-methylpyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)-2-fluoro-N-methylbenzamide

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-isothiocyanato-3-methylpicolinonitrile (Intermediate 6, 2.9 g, 16.57 mmol) and 4-((1-cyanocyclobutyl)amino)-2-fluoro-N-methylbenzamide (Intermediate 21, 2.7 g, 11.05 mmol) in DMA was heated to 65° C. overnight. MeOH (50 mL) and HCl (2M, 70 mL) were added and the mixture was heated to 105° C. for 1 h then cooled to room temperature. Water was slowly added until a yellow solid precipitated and the mixture was stirred at room temperature for 3 h. The solid was filtered, washed with water, dissolved in DCM, dried over sodium sulfate, and absorbed on silica gel. Purification by column chromatography on silica gel eluting with 0 to 100% EtOAc/hexanes afforded a pale yellow solid. This solid was triturated in MeOH, filtered, and dried to afford 1.39 g (29%) of 4-(7-(6-cyano-5-methylpyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)-2-fluoro-N-methylbenzamide as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 8.64 (d, 1H), 8.40 (m, 1H), 8.06 (d, 1H), 7.75 (t, 1H), 7.43 (dd, 1H), 7.32 (dd, 1H), 2.73 (d, 3H), 2.59-2.53 (m, 2H), 2.52 (s, 3H), 2.44-2.23 (m, 2H), 1.91-1.88 (m, 1H), 1.52-1.48 (m, 1H). LCMS [M+1]+ 424.0.

Provenance & Evidence