Phenol → 3-Butyl-2,4-dioxo(1,2-a)-s-triazinobenzimidazole

HRID 972746Notes

Reaction equation

HRID 972746 reaction equation
NC1NC2C=CC=CC=2N=1.[C:11](=O)(OC1C=CC=CC=1)[O:12]C1C=CC=CC=1.C1(O)C=CC=CC=1.C(NCCCC)CCC.[N:43]1[C:47]2[CH:48]=[CH:49][CH:50]=[CH:51][C:46]=2[NH:45][C:44]=1[NH:52][C:53]([NH:55][CH2:56][CH2:57][CH2:58][CH3:59])=[O:54].C(=O)([O-])[O-].[K+].[K+]>C(#N)C1C=CC=CC=1.N1C=CC=CC=1>[CH2:56]([N:55]1[C:11](=[O:12])[N:45]2[C:44](=[N:43][C:47]3[CH:48]=[CH:49][CH:50]=[CH:51][C:46]=32)[NH:52][C:53]1=[O:54])[CH2:57][CH2:58][CH3:59]

Participants

9

Reactant 6

HCID 996PhenolHCID 7597Diphenyl carbonate2×HCID 8148DibutylamineHCID 11430Potassium CarbonateHCID 136242-AminobenzimidazoleHCID 1526721-(2-Benzimidazolyl)-3-n-butylurea

Product 1

HCID 1354875873-Butyl-2,4-dioxo(1,2-a)-s-triazinobenzimidazole

Reagents, catalysts & solvents 2

HCID 1049PyridineSolventHCID 7505BenzonitrileSolvent

Conditions

Temperature
160 °C

Procedure

A mixture of 100 g of 2-aminobenzimidazole and 188 g of diphenyl carbonate, 390 g of phenol and 0.1 g of pyridine was kept for 1 hour at 60°-68° C. and for 15 hours at 70° C. 63 g of dibutylamine were added and the reaction mixture was kept for 1 hour at 70° C. and for 3 hours at 100° C. For the reaction, according to the invention, of the resulting 1-(benzimidazol-2-yl)-3-(butyl)-urea, 241 g of diphenyl carbonate, 200 g of benzonitrile and 0.2 g of potassium carbonate, were added and the mixture was heated to 160° C. for 16 hours. The solvent was largely distilled off in vacuo and the residue was mixed with dibutyl ether. 3-Butyl-2,4-dioxo-1,2,3,4-tetrahydro-s-triazino-[1,2-a]-benzimidazole crystallized out as a crude product. This was separated off and washed with dibutyl ether. For purification, the crude product was boiled with 28 g of potassium hydroxide in 3 liters of water for 90 minutes. The hot solution was filtered. 3-Butyl-2,4-dioxo-1,2,3,4-tetrahydro-s-triazino-[1,2-a]-benzimidazole was isolated from the filtrate by acidification to a pH value of about 5. Melting point 275°-280° C.

Workup

  1. waitthe reaction mixture was kept for 1 hour at 70° C. and for 3 hours at 100° C
  2. customFor the reaction
  3. additionwere added
  4. distillationThe solvent was largely distilled off in vacuo
  5. additionthe residue was mixed with dibutyl ether
  6. custom3-Butyl-2,4-dioxo-1,2,3,4-tetrahydro-s-triazino-[1,2-a]-benzimidazole crystallized out as a crude product
  7. customThis was separated off
  8. washwashed with dibutyl ether
  9. customFor purification
  10. waitthe crude product was boiled with 28 g of potassium hydroxide in 3 liters of water for 90 minutes
  11. filtrationThe hot solution was filtered

Sources & evidence

ORD record
ord-37bf49df03aa4b1eb6e3204980552770
Source dataset
uspto-grants-1977_10
Patent number
US04053598

Reaction notes

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