Ethanol → Tert-butyl 5-(2,4-dichlorophenyl)-7-methyl-2-(5-methyl-1,2,4-oxadiazol-3-yl)imidazo[1,2-a]pyrimidine-6-carboxylate

HRID 1868477Notes

Reaction equation

HRID 1868477 reaction equation
[C:1]([C:3]1[N:4]=[C:5]2[N:10]=[C:9]([CH3:11])[C:8]([C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13])=[C:7]([C:19]3[CH:24]=[CH:23][C:22]([Cl:25])=[CH:21][C:20]=3[Cl:26])[N:6]2[CH:27]=1)#[N:2].[NH2:28]O.Cl.[OH-].[K+].[CH3:33][CH2:34][OH:35]>>[Cl:26][C:20]1[CH:21]=[C:22]([Cl:25])[CH:23]=[CH:24][C:19]=1[C:7]1[N:6]2[CH:27]=[C:3]([C:1]3[N:28]=[C:34]([CH3:33])[O:35][N:2]=3)[N:4]=[C:5]2[N:10]=[C:9]([CH3:11])[C:8]=1[C:12]([O:14][C:15]([CH3:18])([CH3:17])[CH3:16])=[O:13]

Participants

5

Reactant 4

HCID 702EthanolHCID 14797Potassium HydroxideHCID 443297Hydroxyamine hydrochlorideHCID 67021510Tert-butyl 2-cyano-5-(2,4-dichlorophenyl)-7-methylimidazo[1,2-a]pyrimidine-6-carboxylate

Product 1

HCID 57982544Tert-butyl 5-(2,4-dichlorophenyl)-7-methyl-2-(5-methyl-1,2,4-oxadiazol-3-yl)imidazo[1,2-a]pyrimidine-6-carboxylateYield 68%

Conditions

Temperature
70 °C

Procedure

To a stirred solution of tert-butyl 2-cyano-5-(2,4-dichlorophenyl)-7-methylimidazo[1,2-a]pyrimidine-6-carboxylate (50 mg, 0.12 mmol) in EtOH (3 mL) was added NH2OH.HCl (10 mg, 0.12 mmol) and KOH (8.5 mg, 0.12 mmol). After heating to 70° C. for 6 h, the reaction was concentrated under reduced pressure. The resulting residue was suspended in H2O and filtered to collect the desired product as a yellow solid (53 mg). This product was dissolved in PhCH3 (3 mL) and DMA-DMA (0.2 mL) was added. The reaction was heated to 90° C. for 2 h and was concentrated and purified by silica gel chromatography to give tert-butyl 5-(2,4-dichlorophenyl)-7-methyl-2-(5-methyl-1,2,4-oxadiazol-3-yl)imidazo[1,2-a]pyrimidine-6-carboxylate (46 mg, 68% for three steps) as a light yellow solid.

Workup

  1. concentrationthe reaction was concentrated under reduced pressure
  2. filtrationfiltered
  3. customto collect the desired product as a yellow solid (53 mg)
  4. dissolutionThis product was dissolved in PhCH3 (3 mL)
  5. additionDMA-DMA (0.2 mL) was added
  6. temperatureThe reaction was heated to 90° C. for 2 h
  7. concentrationwas concentrated
  8. custompurified by silica gel chromatography

Sources & evidence

ORD record
ord-9fcc0baba2be4e15a8d0f13e65cd09c5
Source dataset
uspto-grants-2009_12
Patent number
US07635699B2

Reaction notes

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