Ethyl bromoacetate → Ethyl 4-[(7,8-dihydro-5-hydroxy-8,8-dimethyl-5-carboethoxymethylnaphth-2-yl)ethynyl]benzoate

Beteiligte Stoffe

Reaktionsschritte

To a refluxing solution of 1.00 g (15.30 mmol) of 20 mesh, granular zinc (activated prior to use by washing with 2% HCl, water, 95% ethanol, acetone, anhydrous Et2O and then dried in vacuum for several hours) in 20 ml of dry benzene was slowly added a mixture of 0.23 ml (1.62 mmol) of ethyl bromoacetate, 0.28 g (0.81 mmol) of ethyl 4-[(5,6,7,8-tetrahydro-8,8-dimethyl-5-oxonaphth-2-yl)ethynyl]benzoate (Compound 1) in 10 ml of dry benzene. The resulting mixture was refluxed for 2 hours, cooled to room temperature and the precipitate filtered through celite. The filtrate was washed with cold 15% H2SO4, sat. aqueous NaHCO3 and brine. The organic phase was dried over Na2SO4 and concentrated in vacuo to a yellow oil. Purification by flash chromatography (silica, 10% EtOAc-hexane) yielded the title compound as a light yellow solid.

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