Sulfuric Acid → HCID 136240437, compound

Temperature

-10 °C

To a 0° C. solution of cyclobutane carboxylic acid (7.50 g, 74.9 mmol) in DCM (100 mL) was added oxalyl chloride (12.00 g, 95 mmol) followed by catalytic amount of DMF. The resultant mixture was stirred at RT for 1 h. The solvent from the reaction mixture was completely evaporated to a light coloured viscous mass. In a different RB flask, a suspension of semicarbazide hydrochloride (9.00 g, 81 mmol) in DCM (100 mL) was treated with triethylamine (18.00 g, 178 mmol) and stirred at −10° C. for 30 minutes. To the reaction mixture was added the acid chloride dissolved in DCM (20 mL) at the same temp and the resultant mixture was stirred at RT over night. The solvent from the reaction mixture was completely removed and the residue was stirred in MeCN (100 mL) for 1 h. The solids were collected by filtration, washed and dried. The solid was transferred to a RB flask and was treated with sodium hydroxide (7.50 g, 188 mmol) and water (20 mL). The resulting reaction mixture was heated at 100° C. for 3 h, cooled to RT, and acidified with conc. sulfuric acid. The solids were collected, washed sparingly with cold water, and dried to provide 3-cyclobutyl-1H-1,2,4-triazol-5(4H)-one, (6.40 g, 61.4% yield) as white solid. 1H NMR (400 MHz, DMSO-d6): δ 11.27 (s, 1H), 11.10 (s, 1H), 2.15 (m, 7H); MS (ESI) m/z: 140.1 (M+H+).

1. customThe solvent from the reaction mixture was completely evaporated to a light
2. customThe solvent from the reaction mixture was completely removed
3. stirringthe residue was stirred in MeCN (100 mL) for 1 h
4. filtrationThe solids were collected by filtration
5. washwashed
6. customdried
7. customThe resulting reaction mixture
8. temperaturewas heated at 100° C. for 3 h
9. temperaturecooled to RT
10. customThe solids were collected
11. washwashed sparingly with cold water
12. customdried

ORD record

ord-75430e75e35648d68bfa06c75af19a90

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09193719B2