反应详情

To a solution of 7-methyl-1H-indazole-5-carbaldehyde (5.0 g, 31.25 mmol) and N-methyl-dicyclohexylamine (113.5 mL, 62.35 mmol) in dry tetrahydrofuran (120 mL) at 0° C., was added 2-(trimethylsilyl)ethoxymethyl chloride (6.65 mL, 39.5 mmol). The icebath was removed and stirring continued for 5 h. The reaction mixture was diluted with ethyl acetate, washed with water (2×), brine (2×), dried over sodium sulfate, and concentrated in vacuo. Column chromatography afforded 8.5 g (93%). 1H-NMR (CD3OD, 300 MHz) δ −0.04 (s, 9H), 0.83-1.01 (m, 2H), 2.60 (s, 3H), 3.22-3.34 (m, 2H), 3.60-3.76 (m, 2H), 5.58 (s, 2H), 7.54 (s, 1H), 8.23 (s, 1H), 8.64 (s, 1H), 9.91 (s, 1H). Mass spec.: 291.33 (MH)+.

1. customThe icebath was removed
2. additionThe reaction mixture was diluted with ethyl acetate
3. washwashed with water (2×), brine (2×)
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated in vacuo
6. customColumn chromatography afforded 8.5 g (93%)