Dimethyl Sulfate → 1,4-Dimethoxynaphthalene

Participants

Reaction Steps

Following the procedure of Evans et al.,23 1,4-naphthoquinone (31, 10.00 g, 63.20 mmol) and Pd/C (10 wt %, 0.994 g) were added to a flame-dried 500 mL round bottom flask at room temperature under Argon. THF (250.0 mL) was then added at room temperature, the reaction vessel was covered in foil, and then purged with H2 for 10 minutes. A balloon filled with H2 was attached and the reaction stirred for 4 hrs at room temperature. The reaction was then purged with Argon before adding NaH (5.66 g, 142 mmol) slowly at 0° C. After 10 minutes Me2SO4 (13.0 mL, 137 mmol) was added slowly at 0° C. The reaction became too thick to stir after adding Me2SO4, and 50 mL of THF were added to facilitate stirring. The dark green mixture was allowed to stir at room temperature for 4 hrs. The reaction was then filtered through celite, washed with brine, dried over MgSO4, and condensed. The resulting solid was then purified by flash chromatography (EtOAc:hexanes) or recrystallized from Et2O:hexanes to provide 32 (11.74 g, 62.42 mmol, 99%) as pink needles.

Provenance & Evidence