Water → Ethyl 3-[3-chloro-6-ethoxy-2-fluoro-5-(2-methyl-1,3-dioxolan-2-yl)phenyl]-4-nitrobutanoate

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Reaction Conditions

Reaction Steps

A solution ethyl (2E)-3-[3-chloro-6-ethoxy-2-fluoro-5-(2-methyl-1,3-dioxolan-2-yl\) phenyl]acrylate (10 g, 28 mmol) (from Step 2) in nitromethane (100 mL) was treated with 1,8-diazabicyclo[5.4.0]undec-7-ene (4.6 mL, 31 mmol) and stirred at 60° C. for 15 h. The reaction mixture was poured into water (400 mL) and extracted with ethyl acetate (2×300 mL). The combined organic extracts were washed with brine, dried over sodium sulfate, filtered, and concentrated to a crude orange oil. The crude material was purified by flash column chromatography using ethyl acetate in hexanes (0%-30%) to give the desired product as a mixture of enantiomers (10.4 g, 89%). 1H NMR (400 MHz, CDCl3) δ 7.52 (d, J=9.1 Hz, 1H), 4.82 (ddd, J=12.5, 7.6, 1.4 Hz, 1H), 4.68 (dd, J=12.5, 7.2 Hz, 1H), 4.54-4.40 (m, 1H), 4.15-3.90 (m, 6H), 3.89-3.75 (m, 2H), 2.85 (ddd, J=16.0, 8.6, 1.4 Hz, 1H), 2.73 (dd, J=16.1, 6.2 Hz, 1H), 1.70 (s, 3H), 1.47 (t, J=7.0 Hz, 3H), 1.21 (t, J=7.1 Hz, 3H). LCMS for C18H24ClFNO7 (M+H)+: m/z=420.1; Found: 420.1.

Provenance & Evidence