Undec-4-ene → Ethyl 6-iodo-1,2-dihydro-2-(trifluoromethyl)-3-quinolinecarboxylate

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Reaction Conditions

Reaction Steps

A mixture of 5-iodo-2-aminobenzaldehyde (24.0 g, 96.7 mmol), diazbicyclo[2.2.2]-undec-7-ene (32.2 g, 212.0 mmol), and ethyl 4,4,4-trifluorocrotonate (35.7 g, 212.0 mmol) in 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (48 mL) was heated at 60° C. for 8 hours. The solution was cooled to room temperature and the solution poured into ethyl acetate-hexanes (1:1, 500 mL). The solution was extracted with 2.5 N aqueous hydrochloric acid (2×200 mL), saturated aqueous ammonium chloride (2×200 mL), dried over sodium sulfate, filtered and concentrated in vacuo. The resulting dark yellow oil was dissolved in hexanes (100 mL) and fine yellow crystals formed upon standing. Vacuum filtration of this suspension yielded ethyl 6-iodo-1,2-dihydro-2-(trifluoromethyl)-3-quinolinecarboxylate as fine yellow crystals (19.3 g, 50% yield): mp 137–138° C. 1H NMR (CDCl3, 300 MHz) 7.62 (s, 1H), 7.36–7.48 (m, 2H), 6.43 (d, J=8.2 Hz), 5.36 (brs, 1H), 5.11 (q, 1H, J=7.1 Hz), 4.25–4.35 (m, 2H), 1.34 (t, 3H, J=7.0 Hz). ESHRMS m/z 395.9716 (M−H, Calc'd 395.9708).

Provenance & Evidence