反应详情

温度

-10 °C

A solution of phosphorus tribromide (5.1 ml) in ether was added during 0.5 hour to a solution of benzyl 2-(2,3-dihydro-6-hydroxymethyl-4-oxo-5-phenyl-4H-1,3-oxazin-3-yl)-2-methylpropanoate (61.1 g) in a mixture of ether and tetrahydrofuran at -78° C. The mixture was then stirred at -10° C. for 4 hours and at room temperature for 1 hour, then washed (water), dried (magnesium sulphate) and evaporated. Purification of the residue by dry column chromatography on silica gel gave benzyl 2-(6-bromomethyl-2,3-dihydro-4-oxo-5-phenyl-4H-1,3-oxazin-3-yl)-2-methylpropanoate (46.1 g), NMR(CDCl3) 1.5(s,6H), 3.8(s,2H), 5.05(s,2H), 5.3(s,2H), 7.2(s,5H).

1. washwashed (water)
2. dry with materialdried (magnesium sulphate)
3. customevaporated
4. customPurification of the residue
5. customby dry column chromatography on silica gel