Perchloric Acid → (S)-ethyl 2-tert-butoxy-2-(6-chloro-7-fluoro-3-methyl-1-(trifluoromethylsulfonyloxy)naphthalen-2-yl)acetate

Participants

Reaction Steps

To a solution of (S)-ethyl 2-(6-chloro-7-fluoro-3-methyl-1-(trifluoromethylsulfonyloxy)naphthalen-2-yl)-2-hydroxyacetate (4.44 g, 9.99 mmol) in tert-butylacetate (100 mL) was added 70% perchloric acid (1.20 mL, 19.98 mmol). The reaction mixture was stirred for 2.5 hours and quenched with solid sodium bicarbonate and stirred for 45 minutes. Water and solid sodium bicarbonate were carefully added and stirred for another 15 minutes. The mixture was diluted with ethyl acetate, washed with saturated bicarbonate solution (2×), brine, dried (MgSO4), filtered, concentrated and purified by flash column chromatography (silica gel, 0 to 20% ethyl acetate/hexanes) to give an pale orange oil (4.26 g). 1H NMR (400 MHz, CDCl3) δ: 7.86 (d, J=7.2 Hz, 4H), 7.74 (d, J=10.2 Hz, 4H), 7.58 (s, 4H), 7.26 (s, 3H), 5.69 (s, 4H), 4.26-4.08 (m, 9H), 2.53 (s, 12H), 1.20 (s, 34H), 1.17 (t, J=7.1 Hz, 13H).

Provenance & Evidence