Nitric Acid → 3-(3-Chloro-1,4-dihydronaphthalen-2-yl)-2-methylacrylic acid

Participants

Reaction Steps

Following a modified procedure by Snyder et al.,33 dimethoxynaphthalene 42a (0.146 g, 0.476 mmol) and Ag(II)O (0.434 g, 3.51 mmol) were combined in a 5 mL round bottom flask and suspended in dioxane (1.5 mL). To the black suspension was added 6 M HNO3 (1.0 mL, 6.0 mmol) at room temperature. The black Ag(II)O quickly dissolved with gas evolution resulting in a yellow solute with yellow precipitate. The reaction was stirred for 10 minutes at room temperature and TLC showed no starting material present. The suspension was first filtered and the filter cake was suspended in CH2Cl2, treated with water, separated, washed with brine, dried, filtered, and condensed. The yellow reaction filtrate was likewise diluted with CH2Cl2, treated with water, separated, washed with brine, dried over MgSO4, filtered, and condensed. The filter cake provided pure 43a that was then purified by recrystallization from acetone/hexane (0.0601 g, 0.22 mmol, 47%). The filtrate provided a less pure 43a that was first purified by flash chromatography (1:4 EtOAc:hexanes 0.5% AcOH) and then recrystallized from acetone/hexane (0.027 g, 0.099 mmol, 21%).

Provenance & Evidence