Semicarbazide hydrochloride → 6-(4-Fluorophenyl)-1,2,4-triazin-3(2H)-one

A mixture of 2,2-diethoxy-1-(4-fluorophenyl)ethanone (5.15 g, 0.0228 mol), semicarbazide hydrochloride (2.6 g, 0.024 mol) in ethanol (50 mL) was stirred at RT overnight, and then heated at 80° C. for 5 h. The mixture was concentrated. The residue was dissolved in acetic acid (50 mL), and heated at 130° C. for 6 h. After cooling, the mixture was concentrated, and the residue was triturated with ethyl ether, filtered, and washed with ether and then hexane. The crystalline solid was collected and dried under high vacuum to the desired product (4.18 g, 96.1%). Analytical LCMS: (M+H)+=192.1.

1. temperatureheated at 80° C. for 5 h
2. concentrationThe mixture was concentrated
3. dissolutionThe residue was dissolved in acetic acid (50 mL)
4. temperatureheated at 130° C. for 6 h
5. temperatureAfter cooling
6. concentrationthe mixture was concentrated
7. customthe residue was triturated with ethyl ether
8. filtrationfiltered
9. washwashed with ether
10. customThe crystalline solid was collected
11. dry with materialdried under high vacuum to the desired product (4.18 g, 96.1%)

ORD record

ord-c89c9e231b4f4bcaa3f1923e89ae249f

Source dataset

uspto-grants-2012_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08143251B2