Formamide → HCID 70025343, compound

HRID 1489612Notes

Reaction equation

HRID 1489612 reaction equation
C([O:3][C:4]([C:6]1[C:14]2[C:9](=[CH:10][CH:11]=[C:12]([O:15][CH3:16])[CH:13]=2)[NH:8][C:7]=1[NH2:17])=O)C.C[O-].[Na+].[CH:21]([NH2:23])=O>>[CH3:16][O:15][C:12]1[CH:11]=[CH:10][C:9]2=[N:8][C:7]3[C:6]([C:4](=[O:3])[NH:23][CH2:21][N:17]=3)=[C:14]2[CH:13]=1

Participants

4

Reactant 3

HCID 713FormamideHCID 10681184HCID 10681184, compoundHCID 10942334Sodium Methoxide

Product 1

HCID 70025343HCID 70025343, compoundYield 72%

Procedure

A solution of 2-amino-5-methoxy-1H-indole-3-carboxylic acid ethyl ester (2.15 g (9.2 mmol), sodium methoxide (0.5 g (9.3 mmol), and formamide (200 mL), is heated under N2 at 220° C. for 1.5 h. The solution is cooled to room temperature, stored for 2.5 days, and filtered. The solvent is evaporated by Kugelrohr distillation at 95° C./0.8 mm. The residual solids are washed with H2O, then heated in 35 mL of boiling N,N-dimethylformamide. The hot suspension is filtered hot over a pad of flash silica gel. The cooled filtrate is concentrated in vacuo to a solid that is sonicated in about 30 mL of MeOH. The solids are filtered, washed with MeOH, and dried to leave 6-methoxy-3H-indolo[2,3-d]pyrimidine-4-one (1.71 g,72%) that is about 83% pure. 1H NMR (DMSO): δ12.16 (1H, br s, exchanges with D2O), 12.04 (1H, br s, exchanges with D2O), 8.08 (1H, d, J=3.4 Hz, exchanges to s with D2O), 7.46 (1H, d, J=1.9 Hz), 7.37 (1H, d, J=8.7 Hz), 6.95 (1H, dd, J=8.8, 2.5 Hz), 3.81 (3 H, s).

Workup

  1. filtrationfiltered
  2. customThe solvent is evaporated by Kugelrohr distillation at 95° C./0.8 mm
  3. washThe residual solids are washed with H2O
  4. temperatureheated in 35 mL of boiling N,N-dimethylformamide
  5. filtrationThe hot suspension is filtered hot over a pad of flash silica gel
  6. concentrationThe cooled filtrate is concentrated in vacuo to a solid
  7. customthat is sonicated in about 30 mL of MeOH
  8. filtrationThe solids are filtered
  9. washwashed with MeOH
  10. customdried

Sources & evidence

ORD record
ord-4d779bc032024e34975de4c006b2553c
Source dataset
uspto-grants-1997_10
Patent number
US05679683

Reaction notes

Loading…