Guanidine Hydrochloride → Ethyl 8-amino-1-methyl-1H-pyrazolo[4,3-h]quinazoline-3-carboxylate

HRID 875101Notes

Reaction equation

HRID 875101 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[C:14]2[CH2:13][CH2:12][C:11](=[CH:15]N(C)C)[C:10](=O)[C:9]=2[N:8]([CH3:20])[N:7]=1)=[O:5])[CH3:2].Cl.[NH2:22][C:23]([NH2:25])=[NH:24]>C(O)C.CC[O-].[Na+]>[NH2:24][C:23]1[N:25]=[CH:15][C:11]2[CH:12]=[CH:13][C:14]3[C:6]([C:4]([O:3][CH2:1][CH3:2])=[O:5])=[N:7][N:8]([CH3:20])[C:9]=3[C:10]=2[N:22]=1

Participants

5

Reactant 2

HCID 5742Guanidine HydrochlorideHCID 67075650ethyl 6-[(dimethylamino)methylene]-1-methyl-7-oxo-4,5,6,7-tetrahydro-1H-indazole-3-carboxylate

Product 1

HCID 57444093Ethyl 8-amino-1-methyl-1H-pyrazolo[4,3-h]quinazoline-3-carboxylateYield 85%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 2723922Sodium ethoxideSolvent

Procedure

16.00 g (0.06 mol) of ethyl-6-[(dimethylamino)methylene]-1-methyl-7-oxo-4,5,6,7-tetrahydro-1H-indazole-3-carboxylate were dissolved in 600 mL of ethanol and 3.90 g of sodium ethylate, and 5.44 g of guanidine hydrochloride were added consecutively. The solution was stirred at reflux for 12 hours. The solvent was then evaporated, the residue redissolved with dichloromethane and washed with water. The organic layer was then dried over anhydrous Na2SO4 and concentrated. The residue was triturated with diethyl ether and the product collected by filtration (85% yield as a white solid).

Workup

  1. temperatureat reflux for 12 hours
  2. customThe solvent was then evaporated
  3. dissolutionthe residue redissolved with dichloromethane
  4. washwashed with water
  5. dry with materialThe organic layer was then dried over anhydrous Na2SO4
  6. concentrationconcentrated
  7. customThe residue was triturated with diethyl ether
  8. filtrationthe product collected by filtration (85% yield as a white solid)

Sources & evidence

ORD record
ord-095b03260e4d4d16a218bbeb4a64c347
Source dataset
uspto-grants-2015_03
Patent number
US08981089B2

Reaction notes

Loading…