反应详情

A 0.3M solution of Compound 2 (0.566 g, 2.99 mmol) in 4M HCl is chilled in an ice bath, and treated with a cold solution of sodium nitrite (1.05 equivalents) in water. The resulting diazonium salt solution is stirred for 15 minutes, and then hypophosphorous acid (50% aqueous solution, Aldrich, 20 equivalents) is added over 5 minutes. The resulting mixture is stirred at room temperature for two hours, then diluted with water. The resulting mixture is neutralized with aqueous sodium carbonate or sodium hydroxide, and extracted twice with ether. The organic extract is washed once with water, once with brine, and dried over anhydrous sodium sulfate. The solution is concentrated in vacuo and the resulting residue is purified by flash chromatography to give 0.38 g (73%) of Compound 3 as a clear, colorless liquid: 1H NMR (CDCl3) 6.80 (td, 1H), 6.58 (m, 1H), 4.00 (s, 3H), 3.87 (s, 3H); 19F NMR (CDCl3) 138.8 (d, 1F), 150.1 (d, 1F). Anal. calc. for C8H8O2F2 : C, 55.19; H, 4.63. Found: C, 54.76; H, 4.63.

1. extractionextracted twice with ether
2. extractionThe organic extract
3. washis washed once with water, once with brine
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationThe solution is concentrated in vacuo
6. customthe resulting residue is purified by flash chromatography