Diphosgene → 5-Phenyl-1,3,4-thiadiazol-2(3H)-one

To a solution of thiobenzhydrazide (3.7 g, 24.34 mmole) in methylene chloride (50 ml), equipped with magnetic stirrer, nitrogen inlet, and an outlet connected to a trap containing a diluted NAOH solution, was added trichloromethyl chloroformate (4 g, 20.2 mmole). The reaction mixture was stirred at room temperature for one hour. The mixture was diluted with methylene chloride (100 ml) and washed with water (3×50 ml) and brine. The organic layer was dried over MgSO4. After the drying agent was filtered off the filtrate was concentrated to a residue. The residue was triturated with hexane and the solid product was collected by suction-filtration to give 3.7 g as a powder. m.p.=140°-143° C.

1. customconnected to a trap
2. additioncontaining a diluted NAOH solution
3. washwashed with water (3×50 ml) and brine
4. dry with materialThe organic layer was dried over MgSO4
5. filtrationAfter the drying agent was filtered off the filtrate
6. concentrationwas concentrated to a residue
7. customThe residue was triturated with hexane
8. filtrationthe solid product was collected by suction-filtration
9. customto give 3.7 g as a powder

ORD record

ord-190f83f2be364f1ab2b210245448176f

Source dataset

uspto-grants-1994_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05292762