反应详情

A mixture of 2,4-dichloro-5,6,7,8-tetrahydroquinazoline [prepared according to the procedure described by M. Botta et al., 40, Tetrahedron, (1984), 3313] (500 mg, 2.4 mmol), phenylhydrazine (270 mg, 2.5 mmol) and N,N-diisopropylethylamine (1 ml, 5.7 mmol) in THF (50 ml) was heated at reflux temperature overnight. The reaction was cooled to room temperature and phosgene (200 ml, 20% in toluene) was added slowly and stirred for an additional 10 min. The mixture was poured into water and extracted with ethyl acetate (3×50 ml). The combined organic layers were washed with brine, dried over Na2SO4 and evaporated under reduced pressure. The residue was triturated with ethanol and filtered to afford 5chloro-2-phenyl-7,8,9,10-tetrahydro-1,2,4-triazolo[4,3-c]quinazolin-3-one, m.p. 205-207° C.

1. customprepared
2. temperatureat reflux temperature overnight
3. extractionextracted with ethyl acetate (3×50 ml)
4. washThe combined organic layers were washed with brine
5. dry with materialdried over Na2SO4
6. customevaporated under reduced pressure
7. customThe residue was triturated with ethanol
8. filtrationfiltered