Tetrahydrofuran → Methyl 2,4,5-triamino-3-fluorobenzoate
Reaction equation
[NH2:1][C:2]1[C:11]([F:12])=[C:10]([NH2:13])[C:9]([N+:14]([O-])=O)=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5].O1CCCC1>CO.[Pd]>[NH2:1][C:2]1[C:11]([F:12])=[C:10]([NH2:13])[C:9]([NH2:14])=[CH:8][C:3]=1[C:4]([O:6][CH3:7])=[O:5]Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 2
Procedure
A mixture of methyl 2,4-diamino-3-fluoro-5-nitrobenzoate (5) (40.0 g, 173.7 mmol) and 5% Pd/C (3.0 g, Type 487; 0.4 mol % Pd relative to starting material), in methanol (300.0 mL) and tetrahydrofuran (300.0 mL) was stirred at 2000 RPM, under hydrogen (˜3.5 bar), at 50° C. in a 1.5 L hydrogenation vessel. After 6 hours the vessel was purged with nitrogen and HPLC analysis indicated that no starting material remained. The mixture was then filtered under nitrogen pressure and the filter washed through with THF (160 mL), to give a clear yellow solution. The solvent was removed by rotary evaporation, to provide methyl 2,4,5-triamino-3-fluorobenzoate (9) 37.5 g (93.3% w/w by NMR) as a solid, yield ˜100%. 1H NMR (400 MHz, d6 DMSO) δ 3.69 (3H, s, NMe), 4.20 (2H, br s, NH2), 5.24 (2H, br s, NH2), 5.70 (2H, br s, NH2), 6.83 (1H, d, J 1, Ar—H). 13C NMR (100 MHz, d6 DMSO) δ 51 (CH3), 98 (C, d, J 5), 110 (CH, d, J 2), 125 (C, d, J 6), 131 (C, d, J 12), 133 (C, d, J 12), 139 (CF, d, J 225), 166 (C═O). vmax/cm-1 3480, 3461, 3373, 3356, 3280, 3163, 1679, 1655, 1314. MS APCI (+) m/z 200 (M+1) detected.
Workup
- customAfter 6 hours the vessel was purged with nitrogen and HPLC analysis
- filtrationThe mixture was then filtered under nitrogen pressure
- washthe filter washed through with THF (160 mL)
- customto give a clear yellow solution
- customThe solvent was removed by rotary evaporation
Sources & evidence
- ORD record
- ord-4c02f0435762423fa018cd291f7f2abc
- Source dataset
- uspto-grants-2013_02
- Patent number
- US08383832B2
Reaction notes
Loading…