Hydrochloric Acid → 3-(2,6-Dichloropyridin-4-yl)-1-methyl-imidazolidine-2,4-dione

Participants

Reaction Conditions

Reaction Steps

TEA (7.2 ml, 51 mmol) was added to a suspension of the HCl salt of sarcosine ethyl ester (3.4 g, 24.5 mmol) in dry DCM (80 ml). The formed triethylamine hydrochloride was filtered off and rinsed with DCM (20 ml). The filtrate was transferred into a 3-necked round bottom flask and cooled to 5° C. A solution of 2,6-dichloropyridin-4-yl isocyanate (10 g, 53 mmol) in DCM (25 ml) was added dropwise over 10 min while keeping the inner temperature below 10° C. After 96 h at RT, the reaction mixture was refluxed for 10 h. After cooling to RT, the solution was washed with brine, dried over MgSO4 and concentrated. The obtained amorphous solid was chromatographed over silica gel (eluent: cyclohexane/EtOAc 80/20 to 50/50) to yield the above titled compound as a white solid (9.9 g). mp=134° C. 1H NMR (CDCl3): 7.75 (2H, s), 4.07 (2H, s), 3.10 (3H, s).

Provenance & Evidence