Acetic Anhydride → (+/-) Ethyl 2-(1-acetoxy-1,2,3,4-tetrahydro-4,4-dimethyl-7-bromo-naphthalen-1-yl)acetate

Beteiligte Stoffe

Reaktionsschritte

To a solution of (±) ethyl 2-(1-hydroxy-1,2,3,4-tetrahydro-4,4-dimethyl-7-bromo-naphthalen-1-yl)acetate (Compound E47, 200.0 mg, 0.586 mmol) and 4-N,N-dimethylaminopyridine (86.0 mg, 0.703 mmol) in 4.0 mL CH2Cl2 at 0° C. was added acetic anhydride (239.3 mg, 2.344 mmol). The resulting solution was warmed to room temperature and stirred overnight. The reaction was warmed to 50° C. for 3 h, cooled to room temperature, and diluted with EtOAc (70 mL). The solution was washed with H2O, saturated aqueous NaHCO3, 10% aqueous HCl, and saturated aqueous NaCl, before being dried over MgSO4. Removal of the solvents under reduced pressure followed by column chromatography afforded the title compound as a colorless oil. 1H NMR (CDCl3): δ1.23 (t, J=7.1 Hz, 3H), 1.30 (s, 3H), 1.31 (s, 3H), 1.76 (t, J=6.9 Hz, 2H), 2.05 (s, 3H), 2.48 (m, 1H), 2.67 (m, 1H), 3.03 (s, 2H), 4.12 (q, J=7.1 Hz, 2H), 7.19 (d, J=8.5 Hz,1H), 7.33 (dd, J=2.1, 8.5 Hz, 1H), 7.45 (d, J=2.1 Hz,1H).

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