反应详情

A 500 milliliter, neck flask equipped with a magnetic stirrer, thermometer, dry ice condenser/drying tube and inlet from a phosgene (COCl2) tank via a calibrated rotameter was charged with 50 milliliters of ethyl acetate saturated with phosgene at 20° C. (approximately 0.5 mole of phosgene). An additional 100 milliliters of ethylacetate was added and 10.0 grams of 5-[1-(2,4-dichlorophenoxy)ethyl]-2-amino-1,3,4-thiadiazole, (prepared above) was added. The resulting emulsion was stirred for 17 hours; and the flask was purged with nitrogen until no COCl2 was detected and a suspension formed. The solid was removed by filtration and dried in a vacuum oven at 80° C. to 5.9 grams of white crystals of 5-[1-(2,4-dichlorophenoxy)ethyl]-1,3,4-thiadiazol-2-yl isocyanate dimer. (Melting point 176°-179° C.).

1. customA 500 milliliter, neck flask equipped with a magnetic stirrer
2. additionwas added
3. customand the flask was purged with nitrogen until no COCl2
4. customa suspension formed
5. customThe solid was removed by filtration
6. dry with materialdried in a vacuum oven at 80° C. to 5.9 grams of white crystals of 5-[1-(2,4-dichlorophenoxy)ethyl]-1,3,4-thiadiazol-2-yl isocyanate dimer