2-甲基-5-溴苯甲酸叔丁酯

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a suspension of anhydrous magnesium sulfate (4.5 g, 37.28 mmol) in dichloromethane (37 mL) is added concentrated H2SO4 (516 μl, 9.302 mmol) and the mixture is stirred vigorously for 15 min. 5-Bromo-2-methyl-benzoic acid (2 g, 9.302 mmol) is added, followed by t-butanol (4.39 mL, 46.51 mmol). The flask is capped tightly and stirred at room temperature for 24 h. After adding saturated sodium bicarbonate, the resulting solution is extracted with ethyl acetate. The organic layer is washed with a saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated. The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7) to furnish 5-bromo-2-methyl-benzoic acid tert-butyl ester. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.59 (s, 9H), 2.51 (s, 3H), 7.08 (d, J=8.1 Hz, 1H), 7.46 (dd, J=8.3, 2.3 Hz, 1H), 7.92 (d, J=2.3 Hz, 1H) The flask is capped tightly stirred at room temperature for 24 h the resulting solution is extracted with ethyl acetate The organic layer is washed with a saturated sodium chloride solution dried over sodium sulfate filtered concentrated The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a suspension of anhydrous magnesium sulfate (4.5 g, 37.28 mmol) in dichloromethane (37 mL) is added concentrated H2SO4 (516 μl, 9.302 mmol) and the mixture is stirred vigorously for 15 min. 5-Bromo-2-methyl-benzoic acid (2 g, 9.302 mmol) is added, followed by t-butanol (4.39 mL, 46.51 mmol). The flask is capped tightly and stirred at room temperature for 24 h. After adding saturated sodium bicarbonate, the resulting solution is extracted with ethyl acetate. The organic layer is washed with a saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated. The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7) to furnish 5-bromo-2-methyl-benzoic acid tert-butyl ester. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.59 (s, 9H), 2.51 (s, 3H), 7.08 (d, J=8.1 Hz, 1H), 7.46 (dd, J=8.3, 2.3 Hz, 1H), 7.92 (d, J=2.3 Hz, 1H) The flask is capped tightly stirred at room temperature for 24 h the resulting solution is extracted with ethyl acetate The organic layer is washed with a saturated sodium chloride solution dried over sodium sulfate filtered concentrated The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a suspension of anhydrous magnesium sulfate (4.5 g, 37.28 mmol) in dichloromethane (37 mL) is added concentrated H2SO4 (516 μl, 9.302 mmol) and the mixture is stirred vigorously for 15 min. 5-Bromo-2-methyl-benzoic acid (2 g, 9.302 mmol) is added, followed by t-butanol (4.39 mL, 46.51 mmol). The flask is capped tightly and stirred at room temperature for 24 h. After adding saturated sodium bicarbonate, the resulting solution is extracted with ethyl acetate. The organic layer is washed with a saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated. The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7) to furnish 5-bromo-2-methyl-benzoic acid tert-butyl ester. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.59 (s, 9H), 2.51 (s, 3H), 7.08 (d, J=8.1 Hz, 1H), 7.46 (dd, J=8.3, 2.3 Hz, 1H), 7.92 (d, J=2.3 Hz, 1H) The flask is capped tightly stirred at room temperature for 24 h the resulting solution is extracted with ethyl acetate The organic layer is washed with a saturated sodium chloride solution dried over sodium sulfate filtered concentrated The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a suspension of anhydrous magnesium sulfate (4.5 g, 37.28 mmol) in dichloromethane (37 mL) is added concentrated H2SO4 (516 μl, 9.302 mmol) and the mixture is stirred vigorously for 15 min. 5-Bromo-2-methyl-benzoic acid (2 g, 9.302 mmol) is added, followed by t-butanol (4.39 mL, 46.51 mmol). The flask is capped tightly and stirred at room temperature for 24 h. After adding saturated sodium bicarbonate, the resulting solution is extracted with ethyl acetate. The organic layer is washed with a saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated. The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7) to furnish 5-bromo-2-methyl-benzoic acid tert-butyl ester. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.59 (s, 9H), 2.51 (s, 3H), 7.08 (d, J=8.1 Hz, 1H), 7.46 (dd, J=8.3, 2.3 Hz, 1H), 7.92 (d, J=2.3 Hz, 1H) The flask is capped tightly stirred at room temperature for 24 h the resulting solution is extracted with ethyl acetate The organic layer is washed with a saturated sodium chloride solution dried over sodium sulfate filtered concentrated The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a suspension of anhydrous magnesium sulfate (4.5 g, 37.28 mmol) in dichloromethane (37 mL) is added concentrated H2SO4 (516 μl, 9.302 mmol) and the mixture is stirred vigorously for 15 min. 5-Bromo-2-methyl-benzoic acid (2 g, 9.302 mmol) is added, followed by t-butanol (4.39 mL, 46.51 mmol). The flask is capped tightly and stirred at room temperature for 24 h. After adding saturated sodium bicarbonate, the resulting solution is extracted with ethyl acetate. The organic layer is washed with a saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated. The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7) to furnish 5-bromo-2-methyl-benzoic acid tert-butyl ester. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.59 (s, 9H), 2.51 (s, 3H), 7.08 (d, J=8.1 Hz, 1H), 7.46 (dd, J=8.3, 2.3 Hz, 1H), 7.92 (d, J=2.3 Hz, 1H) The flask is capped tightly stirred at room temperature for 24 h the resulting solution is extracted with ethyl acetate The organic layer is washed with a saturated sodium chloride solution dried over sodium sulfate filtered concentrated The resulting residue is purified by silica gel flash chromatography (ethyl acetate-heptane, 0:1 to 3:7)