反应详情

Trifluoroacetic acid (31 mL) was added to a suspension of tert-butyl (E)-3-(7-Oxo-5,6,7,8-tetrahydro-1,8-naphthyridin-3-yl)-acrylate (1.1 g, 3.76 mmol; which may be prepared as described in D1, Step 6) in dichloromethane (31 mL). The reaction mixture was stirred at room temperature for 1 hour and concentrated to dryness. The resulting residue was solubilized in a solution of hydrochloric acid in dioxane (4N, 60 mL). After 10 minutes stirring at room temperature, the precipitate was filtered and washed with diethyl ether to afford the title product as a pale yellow solid (4.5 g, quantitative).

1. concentrationconcentrated to dryness
2. stirringAfter 10 minutes stirring at room temperature
3. filtrationthe precipitate was filtered
4. washwashed with diethyl ether