反应详情

A solution of 12.1 g of 207 (42.1 mmol) in 100 ml of anhydrous EtOH was added with 200 mg of PPTS (0.80 mmol, 1.9 mole %) and stirred at RT overnight. Thereafter, the solvent was completely removed under vacuum, and the residue was taken up in 250 ml of a 1:2 mixture of EE/CH. After filtration over a short silica gel column, the eluate was concentrated to obtain 12.8 g of α-methoxycarbamate 45 (40.5 mmol, 96%) as a slightly yellowish oil. An analytical sample was obtained by column chromatography over silica gel (EE/CH 1:2).

1. customThereafter, the solvent was completely removed under vacuum
2. additionthe residue was taken up in 250 ml of a 1:2 mixture of EE/CH
3. filtrationAfter filtration over a short silica gel column
4. concentrationthe eluate was concentrated