Methyl chloroformate → 6-Methoxy-2-(4-methoxy-phenyl)-quinoline

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A 500 mL round-bottom flask is charged with 6-methoxy quinoline-N-oxide (8 g, 0.04566 mol.) and placed under nitrogen. The solid is then dissolved in anhydrous THF (100 mL) and cooled to −78° C. with a dry ice/acetone bath, whereupon some of the dissolved solid begins to precipitate. From an addition funnel, methylchloroformate (4.4 ml, 0.05694 mol.) is added dropwise. The bath is removed 10 minutes after the addition, and replaced after 20 minutes. A dropwise addition of 0.5 M anisylmagnesium bromide (112 mL, 0.0560 mol.) is then made. The bath is removed after the addition and the reaction is allowed to warm to room temperature. The reaction is quenched with 5% sodium bicarbonate solution. The THF is removed in vacuo and the resulting mixture is diluted with water and extracted with methylene chloride. The extracts are collected and dried with anhydrous sodium sulfate and concentrated. The crude product is purified by flash chromatography (2-5% EtOAc/dichloromethane) to yield 6.30 g (52%) of the desired product. 1H NMR: ∂ 8.03-8.11 (m, 4H), 7.78 (d, J=8.8 Hz, 1H), 7.37 (dd, J=9 Hz, 3 Hz, 1H), 7.03-7.07 (m, 3H), 3.94 (s, 1H), 3.88 (s, 1H). LCMS: 2.188 min, 266 (M+).

Herkunft & Nachweise