反应详情

To a stirred solution of 2-hydroxy-5-iodobenzyl alcohol (43.5 g, 174.0 mmol) in acetone (700 mL) was added 85% activated manganese(IV) oxide (5 micron, 50 g, 494.0 mmol) and the solution stirred at room temperature for 16 hours. The manganese oxide was removed by filtration through diatomaceous earth and the filtrate concentrated in vacuo. The product was purified by flash silica chromatography (0-20% ethyl acetate in hexanes) The 2-hydroxy-5-iodobenzaldehyde was obtained as a greenish-yellow solid (24.3 g, 58%). A small amount of the 2-hydroxy-5-iodobenzaldehyde was recrystallized from methanol/water to afford an analytical sample and the remainder of the compound was used without further purification: mp 99-101° C. 1H NMR (CDCl3/300 MHz) 9.83 (s, 1H), 7.79 (d, 1H, J=2.2 Hz), 7.77 (dd, 1H, J=8.7 Hz, J=2.2 Hz), 6.81 (d, 1H, J=8.7 Hz). ESHRMS 246.9229 (M−H Calc'd 246.9256).

1. customThe manganese oxide was removed by filtration through diatomaceous earth
2. concentrationthe filtrate concentrated in vacuo
3. customThe product was purified by flash silica chromatography (0-20% ethyl acetate in hexanes) The 2-hydroxy-5-iodobenzaldehyde