[I:1][C:2]1[CH:15]=[CH:14][C:13]2[C:12]3[C:7](=[CH:8][C:9](I)=[CH:10][CH:11]=3)[CH2:6][CH2:5][C:4]=2[CH:3]=1.B(OC(C)C)(OC(C)C)[O:18]C(C)C.C([Li])CCC.Cl.[OH-].[Na+].OO>C1COCC1.CCCCCC.C1(C)C=CC=CC=1.O>[I:1][C:2]1[CH:3]=[C:4]2[C:13]([C:12]3[CH:11]=[CH:10][C:9]([OH:18])=[CH:8][C:7]=3[CH2:6][CH2:5]2)=[CH:14][CH:15]=18.8 g (20.4 mmol) of 2,7-diiodo-9,10-dihydrophenanthrene are dissolved in 250 ml of THF, and, after addition of 7.0 ml (30.5 mmol) of triisopropyl borate at −70° C., 16.5 ml of a 15 percent solution of n-butyllithium in hexane are added. After 1 h, the batch is hydrolysed using 2 N hydrochloric acid and warmed to room temp. The solution is extracted twice with MTB ether, dried over sodium sulfate, the solvent is removed in vacuo, and the crude product obtained is suspended in 80 ml of toluene and 30 ml of 2 N sodium hydroxide solution with vigorous stirring. After addition of 8 ml of 30 percent hydrogen peroxide, the batch is stirred at 30-40° C. for 30 min with cooling, 200 ml of water are added, and the mixture is acidified using 2 N hydrochloric acid. The aqueous phase is separated off and extracted three times with ethyl acetate. The combined org. phases are washed with dil. ammonium iron(II) sulfate solution and dried over sodium sulfate. The solvent is removed in vacuo, and the residue is filtered through silica gel with dichloromethane, giving 7-iodo-9,10-dihydro-phenanthren-2-ol as a colourless solid.
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