methyl 2-bromofuran-3-carboxylate

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromofuran-3-carboxylic acid methyl ester (3.0 g, 15 mmol, 1.0 eq.), 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (4.5 g, 15 mmol, 1.0 eq.), THF (150 mL) and Na2CO3 (30 mL, 60 mmol, 4.0 eq.) were combined. The mixture was degassed and purged with nitrogen (3×). PdCl2(PPh3)2 (0.3 g, 0.4 mmol, 0.03 eq.) was added, and the mixture was again degassed and purged with nitrogen (3×), then heated at 80° C. overnight. The mixture was then cooled and the layers were separated. The THF layer was diluted with EtOAc (150 mL), washed with saturated aqueous NaCl (80 mL) and dried over Na2SO4. The material was filtered and applied onto a silica gel column and purified by chromatography with PE/EtOAc (20:1 to 10:1) to yield 4-(3-methoxycarbonylfuran-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (3.5 g) as a white solid. The mixture was degassed purged with nitrogen (3×) the mixture was again degassed purged with nitrogen (3×) The mixture was then cooled the layers were separated The THF layer was diluted with EtOAc (150 mL) washed with saturated aqueous NaCl (80 mL) dried over Na2SO4 The material was filtered purified by chromatography with PE/EtOAc (20:1 to 10:1)

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

Procedure: 2-Bromofuran-3-carboxylic acid (5.0 g, 26 mmol, 1 eq.) was dissolved in MeOH (100 mL) and the mixture was degassed and purged with nitrogen (2×). SO2Cl2 (15 mL, 0.2 mol, 7.7 eq.) was added dropwise and the resulting mixture was stirred for two days at room temperature. The mixture was then concentrated and DCM (150 mL) was added. Saturated NaHCO3 (20 mL) was added, and the resulting mixture was stirred at room temperature for 15 minutes. The organic layer was washed with saturated NaHCO3 (20 mL), water (20 mL), and saturated aqueous NaCl (20 mL), then dried over Na2SO4, filtered and concentrated to yield 2-bromofuran-3-carboxylic acid methyl ester (5.0 g) as a brown solid. the mixture was degassed purged with nitrogen (2×) The mixture was then concentrated DCM (150 mL) was added Saturated NaHCO3 (20 mL) was added the resulting mixture was stirred at room temperature for 15 minutes The organic layer was washed with saturated NaHCO3 (20 mL), water (20 mL), and saturated aqueous NaCl (20 mL) dried over Na2SO4 filtered concentrated

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromofuran-3-carboxylic acid methyl ester (3.0 g, 15 mmol, 1.0 eq.), 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (4.5 g, 15 mmol, 1.0 eq.), THF (150 mL) and Na2CO3 (30 mL, 60 mmol, 4.0 eq.) were combined. The mixture was degassed and purged with nitrogen (3×). PdCl2(PPh3)2 (0.3 g, 0.4 mmol, 0.03 eq.) was added, and the mixture was again degassed and purged with nitrogen (3×), then heated at 80° C. overnight. The mixture was then cooled and the layers were separated. The THF layer was diluted with EtOAc (150 mL), washed with saturated aqueous NaCl (80 mL) and dried over Na2SO4. The material was filtered and applied onto a silica gel column and purified by chromatography with PE/EtOAc (20:1 to 10:1) to yield 4-(3-methoxycarbonylfuran-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (3.5 g) as a white solid. The mixture was degassed purged with nitrogen (3×) the mixture was again degassed purged with nitrogen (3×) The mixture was then cooled the layers were separated The THF layer was diluted with EtOAc (150 mL) washed with saturated aqueous NaCl (80 mL) dried over Na2SO4 The material was filtered purified by chromatography with PE/EtOAc (20:1 to 10:1)

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

Procedure: 2-Bromofuran-3-carboxylic acid (5.0 g, 26 mmol, 1 eq.) was dissolved in MeOH (100 mL) and the mixture was degassed and purged with nitrogen (2×). SO2Cl2 (15 mL, 0.2 mol, 7.7 eq.) was added dropwise and the resulting mixture was stirred for two days at room temperature. The mixture was then concentrated and DCM (150 mL) was added. Saturated NaHCO3 (20 mL) was added, and the resulting mixture was stirred at room temperature for 15 minutes. The organic layer was washed with saturated NaHCO3 (20 mL), water (20 mL), and saturated aqueous NaCl (20 mL), then dried over Na2SO4, filtered and concentrated to yield 2-bromofuran-3-carboxylic acid methyl ester (5.0 g) as a brown solid. the mixture was degassed purged with nitrogen (2×) The mixture was then concentrated DCM (150 mL) was added Saturated NaHCO3 (20 mL) was added the resulting mixture was stirred at room temperature for 15 minutes The organic layer was washed with saturated NaHCO3 (20 mL), water (20 mL), and saturated aqueous NaCl (20 mL) dried over Na2SO4 filtered concentrated

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 2-Bromofuran-3-carboxylic acid methyl ester (3.0 g, 15 mmol, 1.0 eq.), 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (4.5 g, 15 mmol, 1.0 eq.), THF (150 mL) and Na2CO3 (30 mL, 60 mmol, 4.0 eq.) were combined. The mixture was degassed and purged with nitrogen (3×). PdCl2(PPh3)2 (0.3 g, 0.4 mmol, 0.03 eq.) was added, and the mixture was again degassed and purged with nitrogen (3×), then heated at 80° C. overnight. The mixture was then cooled and the layers were separated. The THF layer was diluted with EtOAc (150 mL), washed with saturated aqueous NaCl (80 mL) and dried over Na2SO4. The material was filtered and applied onto a silica gel column and purified by chromatography with PE/EtOAc (20:1 to 10:1) to yield 4-(3-methoxycarbonylfuran-2-yl)-3,6-dihydro-2H-pyridine-1-carboxylic acid t-butyl ester (3.5 g) as a white solid. The mixture was degassed purged with nitrogen (3×) the mixture was again degassed purged with nitrogen (3×) The mixture was then cooled the layers were separated The THF layer was diluted with EtOAc (150 mL) washed with saturated aqueous NaCl (80 mL) dried over Na2SO4 The material was filtered purified by chromatography with PE/EtOAc (20:1 to 10:1)

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

Procedure: 2-Bromofuran-3-carboxylic acid (5.0 g, 26 mmol, 1 eq.) was dissolved in MeOH (100 mL) and the mixture was degassed and purged with nitrogen (2×). SO2Cl2 (15 mL, 0.2 mol, 7.7 eq.) was added dropwise and the resulting mixture was stirred for two days at room temperature. The mixture was then concentrated and DCM (150 mL) was added. Saturated NaHCO3 (20 mL) was added, and the resulting mixture was stirred at room temperature for 15 minutes. The organic layer was washed with saturated NaHCO3 (20 mL), water (20 mL), and saturated aqueous NaCl (20 mL), then dried over Na2SO4, filtered and concentrated to yield 2-bromofuran-3-carboxylic acid methyl ester (5.0 g) as a brown solid. the mixture was degassed purged with nitrogen (2×) The mixture was then concentrated DCM (150 mL) was added Saturated NaHCO3 (20 mL) was added the resulting mixture was stirred at room temperature for 15 minutes The organic layer was washed with saturated NaHCO3 (20 mL), water (20 mL), and saturated aqueous NaCl (20 mL) dried over Na2SO4 filtered concentrated