methyl 2,4,5-triamino-3-fluorobenzoate

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. After 6 hours the vessel was purged with nitrogen and HPLC analysis The mixture was then filtered under nitrogen pressure the filter washed through with THF (160 mL) to give a clear yellow solution The solvent was removed by rotary evaporation

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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). νmax/cm−1 3480, 3461, 3373, 3356, 3280, 3163, 1679, 1655, 1314. MS APCI (+) m/z 200 (M+1) detected. After 6 hours the vessel was purged with nitrogen and HPLC analysis The mixture was then filtered under nitrogen pressure the filter washed through with THF (160 mL) to give a clear yellow solution The solvent was removed by rotary evaporation

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. After 6 hours the vessel was purged with nitrogen and HPLC analysis The mixture was then filtered under nitrogen pressure the filter washed through with THF (160 mL) to give a clear yellow solution The solvent was removed by rotary evaporation

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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). νmax/cm-1 3480, 3461, 3373, 3356, 3280, 3163, 1679, 1655, 1314. MS APCI (+) m/z 200 (M+1) detected. After 6 hours the vessel was purged with nitrogen and HPLC analysis The mixture was then filtered under nitrogen pressure the filter washed through with THF (160 mL) to give a clear yellow solution The solvent was removed by rotary evaporation

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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). νmax/cm-1 3480, 3461, 3373, 3356, 3280, 3163, 1679, 1655, 1314. MS APCI (+) m/z 200 (M+1) detected. After 6 hours the vessel was purged with nitrogen and HPLC analysis The mixture was then filtered under nitrogen pressure the filter washed through with THF (160 mL) to give a clear yellow solution The solvent was removed by rotary evaporation

Conditions: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of methyl 2,4,5-triamino-3-fluorobenzoate (9) (7.58 g, 38.1 mmol) in THF (152 mL, 20 vol) was added triethyl orthoformate (20.3 g, 22.8 mL, 137.0 mmol), followed by dropwise addition of H2SO4 (9.33 g, 18 M, 94.1 mmol). The mixture was then heated at 60° C. for 6 hours, at which point no starting material was detected by HPLC analysis. The solid product was filtered and rinsed with THF (150 mL, 20 vol), then transferred to a reaction vessel, suspended in water (150 mL) and the resulting mixture was neutralized to about pH 7.5 with 2 N NaOH. After stirring for 30 minutes, the suspension was filtered and the solid product was dried in a vacuum oven at 55° C., overnight to provide 6-amino-7-fluoro-3H-benzoimidazole-5-carboxylic acid methyl ester (12) 7.5 g, 94% yield (100% area by HPLC). 1H NMR (400 Hz, d6 DMSO) δ 3.53 (1H, br s, NH), 3.85, (3H, s, OMe), 6.10 (2H, br s, NH2), 7.90 (1H, s, Ar—H), 7.20 (1H, s, Ar—H). MS APCI (+) m/z 210 (M+1) detected with MS APCI (+). The solid product was filtered rinsed with THF (150 mL, 20 vol) transferred to a reaction vessel the suspension was filtered the solid product was dried in a vacuum oven at 55° C., overnight