Hydrochloric Acid → 4-Amino-6-methyl-2,5-dihydro-1,2,4-triazin-3-one

HRID 1757521Notes

Reaction equation

HRID 1757521 reaction equation
C([NH:4][N:5]1[CH2:10][C:9]([CH3:11])=[N:8][NH:7][C:6]1=[O:12])(=O)C.Cl.O.[OH-].[Na+]>CO>[NH2:4][N:5]1[CH2:10][C:9]([CH3:11])=[N:8][NH:7][C:6]1=[O:12]

Participants

6

Conditions

Temperature
5 °C

Procedure

85 g of 4-acetylamino-6-methyl-3-oxo-2,3,4,5-tetrahydro-1,2,4-triazine in 250 ml of methanol are stirred together with 63 ml of hydrochloric acid(37%) for 4 hours at 50° C. After cooling to 5° C., 250 ml ofice cold water and 125 ml of sodium hydroxide solution (50%) are added. Thesolvent is removed by evaporation in vacuo. The residue is taken up in 100 ml of ethanol, and the solvent is removed again in vacuo. The residue is taken up in 1200 ml of acetonitrile, undissolved salt precipitates are removed by filtration, the filtrate is concentrated to a small volume, theresidue is caused to crystallise by adding 100 ml of acetic acid ethyl ester at 0° C., and the colourless crystals are filtered off and dried yielding 60.4 g (92% of the theoretical amount) of the title compound having a melting point of 118°-120° C.

Workup

  1. customThesolvent is removed by evaporation in vacuo
  2. customthe solvent is removed again in vacuo
  3. customundissolved salt precipitates
  4. customare removed by filtration
  5. concentrationthe filtrate is concentrated to a small volume
  6. customto crystallise
  7. additionby adding 100 ml of acetic acid ethyl ester at 0° C.
  8. filtrationthe colourless crystals are filtered off
  9. customdried

Sources & evidence

ORD record
ord-798afa20b4f54296a8c63e5ef70863cb
Source dataset
uspto-grants-1995_08
Patent number
US05446154

Reaction notes

Loading…