Iodine → ethyl 6-chloro-8-(methylthio)-2-(trifluoromethyl)-2H-chromene-3-carboxylate

Participants

Reaction Steps

To benzene (solvent) was added ethyl 6-chloro-8-(chlorosulfonyl)-2-(trifluoromethyl)-2H-chromene-3-carboxylate (Step 2, 0.68 g, 1.68 mmol), iodine (0.11 g, 0.84 mmol), and triphenyl phosphine (4.41 g, 16.8 mmol) amd the resulting mixture heated to reflux for 4 h and allowed to cool to RT and stand for 48 h. To this crude reaction was added Et3N (0.58 mL, 0.424 g, 4.20 mmol) and methyl iodide (0.06 mL, 0.13 g, 0.92 mmol). After extractive workup and silica chromatography the title compound was obtained as a yellow, crystalline mass (0.215 g, 36%). 1HNMR (CDCl3-d6/300 MHz) 7.59 (s, 1H), 7.07 (d, J=2.4 Hz, 1H), 6.98 (d, J=2.4 Hz, 1H), 5.78 (q, 1H, J=6.8 Hz), 4.20-4.40 (m, 3H), 2.42 (s, 3H), 1.33 (t, 3H, J=7.3 Hz).

Provenance & Evidence