Methyl 2-bromo-4-methylbenzoate → Methyl 2-isopropyl-4-methylbenzoate

関与物質

反応条件

反応手順

To a stiffed mixture of dibromozinc (39.0 g, 173 mmol, 4.00 equiv) in THF (500 mL) under nitrogen at −48° C. was added dropwise isopropylmagnesium bromide (3 M in THF, 170 mmol) over a period of 30 min Pd(dppf)Cl2 (0.5 g, 0.05 equiv) and methyl 2-bromo-4-methylbenzoate (10.0 g, 43.7 mmol, 1.00 equiv) were added to the above reaction mixture. After stirring for 1 h at −48° C., the reaction mixture was quenched by the careful addition of 500 mL of NH4Cl (aq.). The resulting mixture was extracted with 3×500 mL of ethyl acetate. The combined organic layers were washed with 3×500 mL of brine and concentrated in vacuo. The residue was purified using silica gel column chromatography with petroleum ether (1:1) as eluent. This resulted in 6.50 g (77%) of methyl 2-isopropyl-4-methylbenzoate as a yellow oil.

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