4-(Tert-butyldimethylsilyloxy)-1-(2-fluoro-5-nitrophenyl)-2-methylenebutan-1-ol → 4-(Tert-butyldimethylsilyloxy)-1-(2-fluoro-5-nitrophenyl)-2-methylenebutan-1-one

Participants

Reaction Steps

To a solution of 4-(tert-butyldimethylsilyloxy)-1-(2-fluoro-5-nitrophenyl)-2-methylenebutan-1-ol (0.94 g, 2.64 mmol) from step B in chloroform (88 mL) was added manganese dioxide (3.45 g, 39.7 mmol), and the reaction mixture was heated under reflux for 24 h. The reaction mixture was filtered through a pad of Celite, and the filtrate was evaporated in vacuo. The residue was purified by chromatography eluting with 5-10% ethyl acetate/hexanes to give the title compound as a colorless oil (0.77 g, 82% yield). Some unreacted starting material was also recovered. 1H NMR (500 MHz, CDCl3) δ 8.26 (1H, m), 7.35 (1H, m), 6.18 (1H, s), 5.76 (1H, s), 3.83 (2H, t, J=6.0 Hz), 2.72 (2H, t, J=6.0 Hz), 0.90 (9H, s), and 0.08 (6H, s).

Provenance & Evidence