2,4-Dichloropyrimidine → HCID 178478345, compound

Participants

Reaction Conditions

Reaction Steps

A dried 5-L, three-necked round bottom flask fitted with an overhead stirrer and reflux condenser was charged with a solution of 2,4-dichloropyrimidine (250 g, 1.68 mol) in anhydrous DMSO (2300 mL). 3-Cyclopropyl-1H-pyrazol-5-amine (227.4 g, 1.85 mol) and DIPEA (438 mL, 2.52 mol) were added sequentially at RT. The resulting solution was stirred at 60° C. for 16 h, cooled to RT, and poured into ice water. The precipitated yellow solid was collected by vacuum filtration, washed with water, 1.5 N HCl (3×1 L), and finally with water (4×500 mL). The precipitate was dried by air suction overnight to give 320 g (81%) of 20 as yellow solid: 1H NMR (400 MHz, DMSO-d6): δ 12.19 (s, 1H), 10.29 (s, 1H), 8.15 (s, 1H), 7.0 (br s, 1H), 6.0 (br s, 1H), 1.85-1.92 (m, 1H), 0.91-0.95 (m, 2H), 0.7 (m, 2H); MS (ESI+) m/z: 236 [M+1]+.

Provenance & Evidence