Sulfuric Acid → 9-Chloro-1-(2,4-dichlorophenyl)-6-[1-(1-methylethoxy)propyl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazole

HRID 1399149Notes

Reaction equation

HRID 1399149 reaction equation
[Cl:1][C:2]1[C:10]2[N:9]=[C:8]3[N:11]([C:15]4[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][C:16]=4[Cl:22])[CH2:12][CH2:13][CH2:14][N:7]3[C:6]=2[C:5]([CH:23]([OH:26])[CH2:24][CH3:25])=[CH:4][CH:3]=1.S(=O)(=O)(O)O.C(=O)([O-])O.[Na+].[CH3:37][CH:38](O)[CH3:39]>>[Cl:1][C:2]1[C:10]2[N:9]=[C:8]3[N:11]([C:15]4[CH:20]=[CH:19][C:18]([Cl:21])=[CH:17][C:16]=4[Cl:22])[CH2:12][CH2:13][CH2:14][N:7]3[C:6]=2[C:5]([CH:23]([O:26][CH:38]([CH3:39])[CH3:37])[CH2:24][CH3:25])=[CH:4][CH:3]=1

Participants

5

Reactant 4

HCID 1118Sulfuric AcidHCID 3776IsopropanolHCID 516892Sodium BicarbonateHCID 44156374HCID 44156374, compound

Product 1

HCID 577859379-Chloro-1-(2,4-dichlorophenyl)-6-[1-(1-methylethoxy)propyl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazole

Conditions

Temperature
100 °C

Procedure

To a solution of 1-[9-chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl]propan-1-ol (151.3 mg, 0.368 mmol) in 2-propanol (10.0 mL) was added sulfuric acid (0.45 mL) at 0° C. The reaction mixture was stirred at 100° C. for 16 hrs. The mixture was poured into aqueous saturated sodium hydrogen carbonate and concentrated. The residue was extracted with ethyl acetate (×3). The combined organic layer was washed with brine (×1), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography eluting with a 0-30% ethyl acetate/n-hexane gradient mixture to give the title compound as a colorless amorphous (84.7 mg, 0.187 mmol, 51%).

Workup

  1. concentrationconcentrated
  2. extractionThe residue was extracted with ethyl acetate (×3)
  3. washThe combined organic layer was washed with brine (×1)
  4. dry with materialdried over anhydrous magnesium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo
  7. customThe residue was purified by silica gel column chromatography
  8. washeluting with a 0-30% ethyl acetate/n-hexane gradient mixture

Sources & evidence

ORD record
ord-a07c1915385f404091d2f52e32e58224
Source dataset
uspto-grants-2014_12
Patent number
US08901141B2

Reaction notes

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