1,2-Dibromoethane → 6-(2-Bromoethoxy)-2,2-dimethyl-2,3-dihydro-4H-1,3-benzoxazin-4-one

反応式

[CH3:1][C:2]1([CH3:14])[NH:7][C:6](=[O:8])[C:5]2[CH:9]=[C:10]([OH:13])[CH:11]=[CH:12][C:4]=2[O:3]1.C(=O)([O-])[O-].[K+].[K+].[Br:21][CH2:22][CH2:23]Br>>[Br:21][CH2:22][CH2:23][O:13][C:10]1[CH:11]=[CH:12][C:4]2[O:3][C:2]([CH3:14])([CH3:1])[NH:7][C:6](=[O:8])[C:5]=2[CH:9]=1

参加物

反応物 3

HCID 78391,2-Dibromoethane

HCID 11430Potassium Carbonate

HCID 137543316-hydroxy-2,2-dimethyl-3,4-dihydro-2H-1,3-benzoxazin-4-one

生成物 1

HCID 137544136-(2-Bromoethoxy)-2,2-dimethyl-2,3-dihydro-4H-1,3-benzoxazin-4-one

実験手順

A mixture of 48.2 g of 2,3-dihydro-2,2-dimethyl-6-hydroxy-4H-1,3-benzoxazin-4-one, 70 g of potassium carbonate and 250 ml of 1,2-dibromoethane is refluxed for 4 hours whilst stirring. The semi-liquid reaction mixture is extracted 3 to 4 times whilst hot with 1 liter of methanol each time; the combined methanol extracts are concentrated by evaporation and the residue is recrystallised from methanol. 6-(2-Bromoethoxy)-2,3-dihydro-2,2-dimethyl-4H-1,3-benzoxazin-4-one having a melting point of 190°-195° is obtained.