1,3-Dibromo-5,5-dimethylhydantoin → 4-Bromomethylphenyl 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranoside

반응식

[C:1]([O:4][C@@H:5]1[C@@H:18]([O:19][C:20](=[O:22])[CH3:21])[C@@H:17]([O:23][C:24](=[O:26])[CH3:25])[C@@H:16]([CH2:27][O:28][C:29](=[O:31])[CH3:30])[O:15][C@@H:6]1[O:7][C:8]1[CH:13]=[CH:12][C:11]([CH3:14])=[CH:10][CH:9]=1)(=[O:3])[CH3:2].[Br:32]N1C(C)(C)C(=O)N(Br)[C:34]1=[O:35]>>[C:1]([O:4][C@@H:5]1[C@@H:18]([O:19][C:20](=[O:22])[CH3:21])[C@@H:17]([O:23][C:24](=[O:26])[CH3:25])[C@@H:16]([CH2:27][O:28][C:29](=[O:31])[CH3:30])[O:15][C@@H:6]1[O:7][C:8]1[CH:9]=[CH:10][C:11]([CH2:14][Br:32])=[CH:12][CH:13]=1)(=[O:3])[CH3:2].[CH3:34][OH:35]

참가 물질

반응물 2

HCID 64791,3-Dibromo-5,5-dimethylhydantoin

HCID 541416384-Methylphenyl 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranoside

생성물 2

HCID 887Methanol수율 76%

HCID 539280404-Bromomethylphenyl 2,3,4,6-tetra-O-acetyl-alpha-D-galactopyranoside수율 422.9%

실험 절차

1.4 g (3.2 mmoles) of 4-methylphenyl 2,3,4,6-tetra-O-acetyl-α-D-galactopyranoside (71) and 0.46 g (1.6 mmole) of 1,3-dibromo 5,5-dimethylhydantoine are added in 100 ml of carbone tetrachloride, and the mixture est refluxed under irradiation with light (1 000 W) for 15 minutes. After cooling, the reaction medium is filtered and the filtrate is then evaporated to dryness. 3.5 g of 4-bromomethylphenyl 2,3,4,6-tetra-O-acetyl-α-D-galactopyranoside (72) are isolated by crystallization from methanol (yield=76%).