Triethylamine → ethyl 6-chloro-8-iodo-2-(trifluoromethyl)-2H-chromene-3-carboxylate

Temperature

90 °C

5-Chloro-3-iodosalicylaldehyde (20 g, 70.8 mmol), ethyl 4,4,4-trifluorocrotonate (17.85 g, 106 mmol), and triethylamine (14.33 g, 142 mmol) were dissolved in DMSO (200 mL). The reaction mixture was stirred at 90° C. for three days. The reaction mixture was poured into ethyl acetate (800 mL). It was extracted with 10% HCl (2×200 mL), saturated aqueous NaHCO3 (2×200 mL), and water (2×200 mL). The ethyl acetate phase was dried over MgSO4, filtered and evaporated to yield a brown solid. It was then run through a plug of silica with ethyl acetate-hexane (1:20). The solvent was evaporated to give a yellow solid, that was recrystallized in hexane to afford the ester as a white solid (19.61 g, 64%): mp 92.1–93.9° C. 1H NMR (CDCl3/300 MHz) 7.71 (d, 1H, J=2.2 Hz), 7.56 (s, 1H), 7.20 (d, 1H, J=2.2 Hz), 5.81 (q, 1H, J=6.7 Hz), 4.37–4.29 (m, 2H), 1.35 (t, 3H, J=7.2 Hz). FABLRMS m/z 431.9 (M−H). EIHRMS m/z 431.9269 (M−H, Calc'd. 431.9237).

1. extractionIt was extracted with 10% HCl (2×200 mL), saturated aqueous NaHCO3 (2×200 mL), and water (2×200 mL)
2. dry with materialThe ethyl acetate phase was dried over MgSO4
3. filtrationfiltered
4. customevaporated
5. customto yield a brown solid
6. customThe solvent was evaporated
7. customto give a yellow solid, that
8. customwas recrystallized in hexane

ORD record

ord-ce7a74b4c5cc43a2bc645474df0cd6c8

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07138411B2