Acetic Anhydride → 1-{9-Chloro-1-[6-(dimethylamino)-2-methylpyridin-3-yl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl}propyl acetate

HRID 1399092Notes

Reaction equation

HRID 1399092 reaction equation
[C:1](OC(=O)C)(=[O:3])[CH3:2].[Cl:8][C:9]1[C:17]2[N:16]=[C:15]3[N:18]([C:22]4[C:23]([CH3:31])=[N:24][C:25]([N:28]([CH3:30])[CH3:29])=[CH:26][CH:27]=4)[CH2:19][CH2:20][CH2:21][N:14]3[C:13]=2[C:12]([CH:32]([OH:35])[CH2:33][CH3:34])=[CH:11][CH:10]=1>N1C=CC=CC=1>[C:1]([O:35][CH:32]([C:12]1[C:13]2[N:14]3[CH2:21][CH2:20][CH2:19][N:18]([C:22]4[C:23]([CH3:31])=[N:24][C:25]([N:28]([CH3:30])[CH3:29])=[CH:26][CH:27]=4)[C:15]3=[N:16][C:17]=2[C:9]([Cl:8])=[CH:10][CH:11]=1)[CH2:33][CH3:34])(=[O:3])[CH3:2]

Participants

4

Reactant 2

HCID 7918Acetic AnhydrideHCID 577861351-{9-Chloro-1-[6-(dimethylamino)-2-methylpyridin-3-yl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl}propan-1-ol

Product 1

HCID 577863951-{9-Chloro-1-[6-(dimethylamino)-2-methylpyridin-3-yl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl}propyl acetateYield 76.4%

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

Acetic anhydride (0.30 mL, 3.15 mmol) was added to a stirred solution of 1-{9-chloro-1-[6-(dimethylamino)-2-methylpyridin-3-yl]-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl}propan-1-ol (103 mg, 0.258 mmol) in pyridine (2.0 mL) at room temperature, and the mixture was stirred at room temperature for 6 hr. The mixture was concentrated in vacuo, diluted with saturated aqueous sodium hydrogen carbonate, and extracted with ethyl acetate. The combined organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with a 20-90% ethyl acetate/n-hexane gradient mixture. The filtrate was concentrated in vacuo to give the solid, which was recrystallized from ethyl acetate to give the title compound as a colorless crystal (86.9 mg, 0.197 mmol, 76%)

Workup

  1. concentrationThe mixture was concentrated in vacuo
  2. additiondiluted with saturated aqueous sodium hydrogen carbonate
  3. extractionextracted with ethyl acetate
  4. washThe combined organic layer was washed with brine
  5. dry with materialdried over anhydrous magnesium sulfate
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. customThe residue was purified by flash column chromatography on silica gel eluting with a 20-90% ethyl acetate/n-hexane gradient mixture
  9. concentrationThe filtrate was concentrated in vacuo
  10. customto give the solid, which
  11. customwas recrystallized from ethyl acetate

Sources & evidence

ORD record
ord-220a803b3a3949ef8195b42f9cba7fe4
Source dataset
uspto-grants-2014_12
Patent number
US08901141B2

Reaction notes

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