Hydrochloric Acid → 2-Benzyl-4-bromophenol

Beteiligte Stoffe

Reaktionsschritte

A solution of 13.24 g (99.3 mmol, 4.1 eqv) AlCl3 in 85 ml dry Et2O was added cautiously under stirring to a suspension of 3.91 g (102.9 mmol, 4.2 eqv) LiAlH4 in 100 ml dry Et2O. After complete addition the resulting mixture was stirred for 30 min at rt and then a solution of 6.85 g (24.5 mmol) 4-Bromo-2-(hydroxy-phenyl-methyl)-phenol (19) in 80 ml dry Et2O was added dropwise. The mixture was refluxed for 12 h and after that cooled to 0° C. After adding cautiously 60 ml of a mixture of Et2O/MeOH (1:1), 170 ml 1 N HCl-solution was added and the mixture was extracted with Et2O. The comb. org. fractions were washed with brine, dried over Na2SO4 and evaporated. Column chromatography (CH2Cl2) yielded 4.00 g (15.2 mmol, 62%) 20 as a colorless liquid: Rf (CH2Cl2) 0.41; 1H NMR (500 MHz, CDCl3) δ 3.95 (s, 2H), 4.64 (s, 1H), 6.67 (dd, 1H, J1=8.04 Hz, J2=0.79 Hz), 7.23 (m, 5H), 7.31 (m, 2H); LRMS (EI) m/z 265 (17), 264 (98), 263 (21), 262 (100), 186 (53), 184 (49), 183 (78), 182 (18), 181 (27), 165 (49), 153 (23), 152 (26), 91 (29), 84 (14), 78 (25), 77 (31), 76 (16), 63 (15); HRMS (EI) Calcd. for C13H11BrO: 261.999326. Found: 261.998568.

Herkunft & Nachweise