Hydrochloric Acid → 2-(Benzyloxy)-4-iodophenol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 2-(benzyloxy)phenol (63.7 ml, 364 mmol) in MeOH (1050 ml) was cooled to −10° C. and sodium iodide (54.5 g, 364 mmol) and sodium hydroxide (382 ml, 764 mmol) were added (NaOH over 5 min, temp to 10° C. and dark solution with NaOH addition). Cooled back to <5° C. and added sodium hypochlorite (247 ml, 400 mmol) dropwise, keeping the temperature at <5° C. After 10 min, removed 500 mL MeOH by rotary evaporation, then added MTBE (730 mL) and 2 N HCl (909 ml, 1818 mmol), washed with 1 N Na2S2O3 (130 mL×3; lighter each time) and brine (64 mL), dried (Na2SO4), conc, and flushed with cyclohexane (100 mL) to a crude yellow solid. Added cyclohexane (130 mL), heated to 55° C. (yellow solution), then cooled slowly, seeding at 45° C. (˜50 mg-solution) and 40° C. (˜50 mg, slurry developed). Continued cooling to room temperature (˜20-25° C.) and stirred vigorously overnight. Filtered, washing with cyclohexane (64 mL), giving crop 1 material (69.93 g, 59%, very pure by 1H NMR, slightly off-white solid). Concentrated the mother liquors to ˜70 mL, seeded, aged 1 h, and sticky dark material was precipitating with product. Added MTBE (7 mL), sonicated (good for color dissolution), stirred 20 min, and filtered. Washed with 10% MTBE/cyclohexane (32 mL), giving crop 2 material (4.65 g, some small impurities by 1H NMR). Overall, isolated 2-(benzyloxy)-4-iodophenol (74.6 g, 229 mmol, 62.9% yield). 1H NMR (501 MHz, DMSO-d6) δ 9.33 (s, 1H), 7.49-7.42 (m, 2H), 7.42-7.35 (m, 2H), 7.35-7.29 (m, 1H), 7.24 (d, J=2.0 Hz, 1H), 7.09 (dd, J=8.3, 2.1 Hz, 1H), 6.64 (d, J=8.3 Hz, 1H), 5.09 (s, 2H).

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