Formamidine acetate → tert-Butyl 7,8-dihydropyrido[4,3-d]pyrimidine-6(5H)-carboxylate

HRID 132859

Reaction equation

HRID 132859 reaction equation
C(O)(=O)C.[CH:5]([NH2:7])=[NH:6].[O-]CC.[Na+].O=[C:13]1[CH2:18][CH2:17][N:16]([C:19]([O:21][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:20])[CH2:15][C:14]1=[CH:26]N(C)C>C(O)C>[C:22]([O:21][C:19]([N:16]1[CH2:17][CH2:18][C:13]2[N:6]=[CH:5][N:7]=[CH:26][C:14]=2[CH2:15]1)=[O:20])([CH3:25])([CH3:23])[CH3:24]

Participants

5

Reactant 3

HCID 160693Formamidine acetateHCID 2723922Sodium ethoxideHCID 53395404tert-butyl 3-[(dimethylamino)methylene]-4-oxotetrahydro-1(2H)-pyridinecarboxylate

Product 1

HCID 22707088tert-Butyl 7,8-dihydropyrido[4,3-d]pyrimidine-6(5H)-carboxylate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Procedure

Formamidine acetate (472 mg, 4.52 mmol) in 15.0 mL of absolute ethanol was treated with sodium ethoxide (21 wt % solution in ethanol; 1.7 mL). After 30 min, a solution of the product from Step A above (1.15 g) in 8 mL of absolute ethanol was added, and the mixture was warmed at reflux for 18 h. The dark solution was cooled to room temperature and concentrated under reduced pressure, and the residue was partitioned between ethyl acetate and water. The organic layer was separated, washed with brine, dried over magnesium sulfate and concentrated to an orange oil. Purification by flash chromatography (silica gel; 2% methanol/dichloromethane as eluant) afforded the title compound as a light yellow gum.

Workup

  1. temperaturethe mixture was warmed
  2. temperatureat reflux for 18 h
  3. concentrationconcentrated under reduced pressure
  4. customthe residue was partitioned between ethyl acetate and water
  5. customThe organic layer was separated
  6. washwashed with brine
  7. dry with materialdried over magnesium sulfate
  8. concentrationconcentrated to an orange oil
  9. customPurification by flash chromatography (silica gel; 2% methanol/dichloromethane as eluant)

Sources & evidence

ORD record
ord-66ae1acf66014a01b5eaced42a3466dd
Source dataset
uspto-grants-2008_06
Patent number
US07388019B2

Linked notes

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