Bromine → HCID 21470010, Verbindung
Reaktionsgleichung
[Br:1]Br.[Cl-].[OH:4][C:5]1[CH:10]=[CH:9][C:8]([O:11][CH3:12])=[CH:7][C:6]=1[CH2:13][P+:14]([C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1)([C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1>CO>[Br-:1].[Br:1][C:10]1[C:5]([OH:4])=[C:6]([CH2:13][P+:14]([C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)([C:27]2[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=2)[C:21]2[CH:22]=[CH:23][CH:24]=[CH:25][CH:26]=2)[CH:7]=[C:8]([O:11][CH3:12])[CH:9]=1Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
In the course of 1.5 hours, at 5°, 13 g of bromine are added dropwise to a solution of 35 g of [(2-hydroxy-5-methoxy-phenyl)methyl]-triphenyl-phosphonium chloride in 700 ml of methanol. The solution is concentrated in vacuo at 20° to 110 ml, 220 ml of ethyl acetate are added thereto in the course of 2 hours, the resulting yellow suspension is stirred for 2 hours at 0°, and the slightly yellow crystals are filtered off with suction and recrystallised from methanol. A mixture of colourless crystals (m.p.: 210°) which according to AgNO3 titre comprises 22.4 percent by weight [(3-bromo-2-hydroxy-5-methoxy-phenyl)methyl]-triphenyl-phosphonium chloride and 77.6 percent by weight [(3-bromo-2-hydroxy-5-methoxy-phenyl)methyl]-triphenyl-phosphonium bromide is obtained; yield 76% of the theoretical yield.