Trifluoroacetic acid → 1-(5-Bromo-2-methoxy-benzyl)-naphthalene

Participants

Reaction Steps

3.06 g (80.89 mmol, 10.48 eq.) NAB4 (granules) were added slowly to 50 ml Trifluoroacetic acid at 0° C. To this mixture a solution of 2.65 g (7.72 mmol) (5-Bromo-2-methoxy-phenyl)-napthalen-1-yl-methanol (62) in 30 ml dry CH2Cl2 was added which led to an brownish mixture. After stirring this mixture for 19 h at r.t. it was diluted with water and cooled again to 0° C. At this temperature NaOH-pellets were added carefully to adjust the pH to 10 before the solution was extracted with ether. The comb. org. fractions. were washed with brine, dried over Na2SO4 and evaporated. Column chromatography (CH2Cl2) yielded 2.42 g (7.39 mmol, 95.72%) 1-(5-Bromo-2-methoxy-benzyl)-naphthalene (63) as a pale yellow oil. Rf (CH2Cl2)=0.73. 1H-NMR (400 MHz, CDCl3): δ=3.84 (s, 3H, OMe), 4.35 (s, 2H), 6.76 (d, 1H, J=8.72 Hz), 6.91 (d, 1H, J=2.53 Hz), 7.20 (dm, 1H, J1=6.82 Hz), 7.26 (dd, 1H, J1=8.84 Hz, J2=2.53 Hz), 7.38 (m, 1H), 7.41-7.49 (m, 2H), 7.74 (d, 1H, J=8.34 Hz), 7.84 (m, 1H), 7.91 (m, 1H). MS (EI): m/z=329 (18), 328 (97), 327 (20), 326 (100), 248 (16), 247 (35), 232 (22), 231 (25), 216 (20), 215 (41), 203 (17), 202 (25), 142 (21), 141 (61), 115 (10), 101 (14). HR-MS (EI): Calcd. for C18H15BrO: 326.030626. Found: 326.030567.

Provenance & Evidence