Tetrahydrofuran → 6-chloro-3-methylspiro[1H-quinazoline-4,5'-imidazolidine]-2,2',4'-trione

HRID 34544

Reaction equation

HRID 34544 reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[N:7]([C:11](=[O:14])[NH:12][CH3:13])[C:6](=[O:15])[C:5]2=O.Br.C(S[C:21](=[NH:23])[NH2:22])C.C(N(CC)CC)C.[O:31]1CCCC1>>[Cl:1][C:2]1[CH:3]=[C:4]2[C:5]3([C:6](=[O:15])[NH:23][C:21](=[O:31])[NH:22]3)[N:12]([CH3:13])[C:11](=[O:14])[NH:7][C:8]2=[CH:9][CH:10]=1

Participants

5

Reactant 4

HCID 8028TetrahydrofuranHCID 8471TriethylamineHCID 200213S-Ethylisothiuronium bromideHCID 14229949HCID 14229949, compound

Product 1

HCID 142299686-chloro-3-methylspiro[1H-quinazoline-4,5'-imidazolidine]-2,2',4'-trioneYield 53.1%

Procedure

5-Chloro-1-methylcarbamoylisatin (4.0 g) is dissolved in tetrahydrofuran (40 ml) and thereto are added 2-ethylisothiourea hydrobromide (4.0 g) and triethylamine (3.0 ml), and the mixture is stirred at room temperature for one hour. The reaction mixture is concentrated under reduced pressure to remove the solvent. To the residue [i.e. 6-chloro- 3-methyl-4-hydroxy-4-(2-ethylisothioureido)carbonyl-2-oxo-1,2,3,4-tetrahydroquinazoline] is added 10% hydrochloric acid (50 ml), and the mixture is stirred at 70°-80° C. for 3 hours. After cooling, the precipitates are taken by filtration to give 6-chloro-3-methyl-spiro[1,2,3,4-tetrahydroquinazoline-4,4'-imidazolidine]-2,2',5'-trione (2.5 g, yield 53.1%).

Workup

  1. concentrationThe reaction mixture is concentrated under reduced pressure
  2. customto remove the solvent
  3. additionTo the residue [i.e. 6-chloro- 3-methyl-4-hydroxy-4-(2-ethylisothioureido)carbonyl-2-oxo-1,2,3,4-tetrahydroquinazoline] is added 10% hydrochloric acid (50 ml)
  4. stirringthe mixture is stirred at 70°-80° C. for 3 hours
  5. temperatureAfter cooling
  6. filtrationthe precipitates are taken by filtration

Sources & evidence

ORD record
ord-850eaaccdc6e40e698af6ee15b322d76
Source dataset
uspto-grants-1988_08
Patent number
US04762839

Linked notes

Loading…