Under nitrogen, cyclohexane bromide (5.96 g, 36.55 mmol) was added dropwise to a mixture of magnesium chips (0.87 g, 36.25 mmol) and iodine crystals in anhydrous diethyl ether, starting with 1 mL and adding the remainder after the reaction had started, while maintaining gentle reflux. The mixture was stirred at room temperature until all the magnesium was dissolved (1 h). The resulting cyclohexyl magnesium bromide solution was cooled to 0 °C. A solution of 2-methyl 2-oxo-2-phenylacetate (3.0 g, 18.29 mmol) in tetrahydrofuran (20 mL) was added dropwise. The reaction mixture was allowed to reach room temperature and stirred for 2 h.
The mixture was then cooled to 0°C, quenched by slow addition of a saturated ammonium chloride solution, and extracted with ethyl acetate. The organic layer was washed with water and brine, dried over Na₂SO₄, and the solvent was evaporated under reduced pressure to obtain a crude residue, which was purified by silica gel column chromatography (1.5% ethyl acetate in petroleum ether) to give a yellow, viscous Methyl cyclohexylphenylglycolate, liquid (2.6 g, 57%).
