Dichloromethane → Rac-(cyclohex-2-enyloxy)-(3,4-dichloro-phenyl)-acetic acid methyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a dry 25 mL round bottom flask under argon was placed diazo-(3,4-dichloro-phenyl)-acetic acid methyl ester (from Example 1, 552 mg, 2.25 mmol), dichloromethane (10 mL) and rac-2-cyclohexen-1-ol (0.45 mL, 4.51 mmol). The solution was stirred at 25° C. and then the rhodium (II) acetate dimer (20 mg, 0.045 mmol) was added. Gas evolution began immediately and the color changed from bright yellow to an aquagreen color. After the solution was stirred at 25° C. for a period of 1 h, it was poured into water and the layers were separated. The aqueous layer was washed with dichloromethane (3×15 mL), then the combined organic layers were dried over sodium sulfate and evaporated under reduced pressure. The residual oil was purified by flash chromatography (Merck Silica gel 60, 230-400 mesh, 98/2 hexanes/ethyl acetate to afford rac-(cyclohex-2-enyloxy)-(3,4-dichloro-phenyl)-acetic acid methyl ester (552 mg, 78% yield) as a light yellow oil: EI-HRMS m/e calcd for C15H16Cl2O3 (M+) 314.0468, found 314.0476.

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