Diethyl benzylphosphonate → HCID 86673406, compound

Participants

Reaction Steps

To a solution of diethyl benzylphosphonate (4.57 mL, 21.91 mmol) in dimethylformamide (50 mL) at room temperature was added sodium methoxide (2.367 g, 43.8 mmol) and 18-Crown-6 (2.316 g, 8.76 mmol). After stirring at room temperature for 5 min, the reaction was cooled to 0° C. and treated with 6-bromopicolinaldehyde (4.89 g, 26.3 mmol) as a solid in one portion. The ice bath was removed and the reaction stirred at room temperature for 1 h. The reaction was gradually warmed to 120° C. and held there for 2 h. The reaction was cooled to room temperature and poured into water (500 mL) with vigorous stirring. The resulting suspension was extracted with diethyl ether, washed with water (3×), then brine, dried over magnesium sulfate, and concentrated to an oil. The oil was dissolved in hexanes and reconcentrated to give something that appeared to be crashing out as a solid. The resulting residue (solid in oil) was suspended in ethanol, concentrated, and pumped under high vacuum to give a dark-colored, moist solid. The resulting residue was suspended in ethanol (total volume (solid+solution)=20 ml). The resulting suspension was placed in the freezer and held there overnight. The resulting precipitate was collected by filtration to give 2.46 g (43%) as a faint tan powder. 1H-NMR (CDCl3, 500 MHz) δ 7.69 (d, J=16.2, 1H), 7.60 (d, J=8.9, 2H), 7.53 (dd, J=7.9, 7.6, 1H), 7.41 (dd, J=7.6, 7.3, 2H), 7.31-7.38 (m, 3H), 7.11 (d, J=16.2, 1H). 13C-NMR (CDCl3, 126 MHz) δ 157.2, 142.3, 138.8, 136.3, 134.5, 128.9, 128.8, 127.4, 126.4, 126.2, 120.7.

Provenance & Evidence