To a solution of 0.23 g (0.54 mmol) of ethyl 4-[(5,6,7,8-tetrahydro-5-hydroxy-8,8-dimethylnaphth-2-yl)ethynyl]benzoate (Compound 9) in 4 ml of dry CH2Cl2 was added 0.06 ml of triethylamine (0.81 mmol). The solution was flushed with nitrogen and then 0.12 g (0.81 mmol) of chlorotrimethylsilane was slowly added by syringe. The mixture was stirred at room temperature (flushed with nitrogen) for 30 minutes, concentrated in vacuo to an oil and purified by flash chromatography (silica, 10% EtOAc-hexane) to yield the title compound as a clear oil.
