Hydrochloric Acid → 3-Chloro-5-ureido-5,6,7,8-tetrahydroquinoline-5-carboxylic acid

HRID 1591256Notes

Reaction equation

HRID 1591256 reaction equation
[Cl:1][C:2]1[CH:3]=[N:4][C:5]2[CH2:6][CH2:7][CH2:8][C:9]3([C:16]=2[CH:17]=1)[C:13](=[O:14])[NH:12][C:11](=[O:15])[NH:10]3.[OH-].[Na+].Cl.[O-:21]C#N.[K+].[O-]C#N>O>[Cl:1][C:2]1[CH:3]=[N:4][C:5]2[CH2:6][CH2:7][CH2:8][C:9]([NH:10][C:11]([NH2:12])=[O:15])([C:13]([OH:21])=[O:14])[C:16]=2[CH:17]=1

Participants

7

Reactant 5

HCID 313Hydrochloric Acid2×HCID 14798Sodium HydroxideHCID 109995133-Chlorospiro-[5,6,7,8-tetrahydroquinolin-5,4'-imidazolidine]-2',5'-dioneHCID 11378442Potassium cyanate2×HCID 178513472HCID 178513472, compound

Product 1

HCID 117476283-Chloro-5-ureido-5,6,7,8-tetrahydroquinoline-5-carboxylic acidYield 67.3%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
20 °C

Procedure

3-Chlorospiro-[5,6,7,8-tetrahydroquinolin-5,4'-imidazolidine]-2',5'-dione (133.2 grams, 0.53 mol) and sodium hydroxide (70 grams, 1.75 mol) in water (500 ml) was refluxed for 48 hours. The reaction was cooled to 20° C. and the pH adjusted to about 7 by the addition of HCl (first conc. HCl, then 3N as neutrality is reached). Potassium cyanate (8.59 grams, 1.06 mol) was added carefully in portions over 30 minutes and the reaction stirred at room temperature for 4 hours, then at 60° C. overnight. Additional potassium cyanate (40 grams, 0.53 mol) was added in the morning and the reaction stirred for 48 hour at 60° C. During the reaction with cyanate, the pH of the reaction became basic and was periodically adjusted to ca. pH 7.5. The reaction mixture was stirred with a small amount of activated carbon and filtered. The filtrate was cooled to 5° to 10° C. and acidified to pH 3.5 with 6N HCl. The precipitate was collected, washed with water and slurried in acetone (500 ml). The product was filtered and dried in vacuo. 96 grams; 67.3% yield. mp 188°-89.5° C. NMR (DMSO-d6, 300 MHz) δ8.43 (d, 1), 7.94 (d, 1), 6.92 (s, 1), 5.72 (s, 1), 2.83 (t, 2), 2.26 (m, 1), 2.12 (m, 1), 1.90 (m, 2).

Workup

  1. customat 60° C.
  2. customovernight
  3. stirringthe reaction stirred for 48 hour at 60° C
  4. stirringThe reaction mixture was stirred with a small amount of activated carbon
  5. filtrationfiltered
  6. temperatureThe filtrate was cooled to 5° to 10° C.
  7. customThe precipitate was collected
  8. washwashed with water
  9. filtrationThe product was filtered
  10. customdried in vacuo

Sources & evidence

ORD record
ord-19f6631d835b4404a91bd17a98b4610f
Source dataset
uspto-grants-1993_04
Patent number
US05206367

Reaction notes

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