[Mg].Br[C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][CH:12]=1)[CH:9]=[C:8]([C:13]([O:15]C)=[O:14])[CH:7]=[CH:6]2.O>C1COCC1.[Cl-].[Zn+2].[Cl-]>[CH:9]1[C:10]2[C:5](=[CH:4][CH:3]=[CH:12][CH:11]=2)[CH:6]=[CH:7][C:8]=1[C:13]([OH:15])=[O:14]33.3 g (79 mmol) of the compound produced in part (a) above, dissolved in 200 ml of THF are slowly added to a suspension of magnesium (2.9 g, 118 Atg) in 60 ml of THF. Once the addition is complete, the mixture is heated at reflux for 2 hours at which point the temperature of the mixture is permitted to return to ambient temperature. 10.8 g (79 mmol) of anhydrous zinc chloride are added and the mixture is stirred for one hour at ambient temperature, at which point 10.5 g (39.5 mmol) of methyl 6-bromo-2-naphthoate and 500 mg of NiCl2 /DPPE complex are added. This mixture is then stirred for 2 hours at ambient temperature, poured into water, extracted with CH2Cl2, dried and evaporated. The residue is chromatographed on a silica column (eluant: mixture of heptane (70%) and ether (30%). 18.5 (90%) of the methyl ester of 6-[3-(1-adamantyl)-4 ™tert.butyldimethylsilyloxyphenyl]-2-naphthoic acid are obtained. Melting point: 152°-153° C.
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