p-Toluenesulfonic acid → 3-methoxy-1,7-naphthyridin-8(7H)-one
Reaction equation
CO[CH:3](OC)[CH2:4][C:5]1[C:6]([C:13]([NH2:15])=[O:14])=[N:7][CH:8]=[C:9]([O:11][CH3:12])[CH:10]=1.CC1C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[CH3:12][O:11][C:9]1[CH:8]=[N:7][C:6]2[C:13](=[O:14])[NH:15][CH:3]=[CH:4][C:5]=2[CH:10]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a mixture of 3-(2,2-dimethoxyethyl)-5-methoxypicolinamide (6.74 g, 28.1 mmol) in toluene (112 ml) was added 4-methylbenzene sulfonic acid (monohydrate; 0.534 g, 2.81 mmol). The reaction mixture was heated to reflux for 20 h. The reaction mixture was cooled to rt and concentrated in vacuo to a volume of ca. 15 mL. The residue was triturated with heptanes and filtered to afford 3-methoxy-1,7-naphthyridin-8(7H)-one (4.53 g, 25.7 mmol, 92% yield) as a crude, tan solid that was advanced without further purification. MS m/z=177.1 [M+H]+
Workup
- temperatureThe reaction mixture was heated
- temperatureto reflux for 20 h
- concentrationconcentrated in vacuo to a volume of ca. 15 mL
- customThe residue was triturated with heptanes
- filtrationfiltered
Sources & evidence
- ORD record
- ord-e8fe0ca838fe4ba5b026890fa89a13ab
- Source dataset
- uspto-grants-2015_07
- Patent number
- US09085576B2
Reaction notes
Loading…