Boron tribromide → 2,4,6-Trichloropyrimidin-5-ol

関与物質

反応手順

Under an atmosphere of nitrogen a solution of 2,4,6-trichloro-5-methoxy-pyrimidine (4.0 g, 18.7 mmol) in DCM (200 mL) was cooled to 0° C. and treated with boron tribromide (neat, 6.6 mL, 65 mmol) dropwise. After stirring for 18 hours at room temperature LCMS analysis indicated complete reaction. The reaction mixture was cooled and diluted with methanol (25 mL, CARE, EXOTHERM!) and the reaction mixture diluted with water (200 mL). The aqueous layer was washed with DCM and the combined organic extracts dried (Na2SO4) filtered and concentrated in vacuo to give 2,4,6-trichloro-5-hydroxy-pyrimidine as a pale tan solid (2.55 g, 71%). 13C NMR (DMSO-d6): 149.23 (C), 145.25 (C), 145.08 (C). LCMS: RT=2.65/2.77 [M−H]−=197/199.

情報源と証拠