Water → HCID 178512678, compound

Participants

Reaction Steps

Guanidine nitrate (244 g.) was slurried in dimethylformamide (500 ml., dried over molecular sieve) and sodium hydride paste (58 g. of a 63% w/w dispersion in oil) was added over 30 minutes with external cooling in an acetone/solid CO2 bath to maintain the internal temperature at 25°-30°. The mixture was stirred for 30 minutes at 25° then cooled to 20°. 5-Chloro-3-chloromethyl-1,2,4-thiadiazole (84.5 g.) was added at 20°-25° over 20 minutes with external cooling at 5°-10°. The mixture was stirred for 20 minutes at 25° then poured into water (5000 ml.) and extracted with ethyl acetate (2×5000 ml.). The combined upper layers were extracted with 2 N HCl (2×500 ml.) and the combined acid extracts were basified with 2 N NaOH. The product was filtered off, washed with water, sucked dry and then dried over P2O5 at 1 m.m. to give 3-chloromethyl-5-guanidino-1,2,4-thiadiazole.

Provenance & Evidence