Urea → HCID 23449997, compound

Participants

Reaction Steps

To a 250 mL round bottomed flask was charged 2.0 g of 2-fluoro-3-methoxy-benzoic acid in 80 mL of anhydrous toluene. Triethylamine (1.15 eq, 1.88 mL) was added after drying over molecular sieves. After dropwise addition of diphenylphosphoryl azide (1.15 eq, 2.8 mL) in 12 mL toluene, the reaction was stirred for 20 minutes at ambient temperature. The reaction was heated to 95° C., then stirred for 20 minutes. After the reaction was cooled to ambient temperature, 1,2-diamino-2-methyl-propane (1.15 eq, 1.42 mL) was added in 20 mL CH2Cl2. Urea formation was complete in 2 hours. The reaction mixture was diluted with 100 mL H2O and extracted with EtOAc (3×100 mL). The combined organics were washed with brine (1×100 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The residue was filtered over a pad of silica (65×40 mm), impurities eluted with 100%EtOAc, the product eluted with 50%MeOH/CH2Cl2. The eluent was concentrated in vacuo to yield 1.85 g (62%) of 1-(2-Amino-2-methyl-propyl)-3-(2-fluoro-3-methoxy-phenyl)-urea as a brown solid. 1H NMR (CDCl3) δ: 7.61 (dt,1H), 7.0 (dt,1H), 6.61 (dt,1H), 5.75 (bs,1H), 3.87 (s,3H), 3.14 (d,2H), 1.12 (s,6H); MS (CI) m/z 256 (MH+).

Provenance & Evidence