Hydrogen Bromide → 5-hydroxy-2,3-dihydro-1H-indene-1-carboxylic acid
Reaction equation
C[O:2][C:3]1[CH:4]=[C:5]2[C:9](=[CH:10][CH:11]=1)[CH:8]([C:12]([OH:14])=[O:13])[CH2:7][CH2:6]2.Br>>[OH:2][C:3]1[CH:4]=[C:5]2[C:9](=[CH:10][CH:11]=1)[CH:8]([C:12]([OH:14])=[O:13])[CH2:7][CH2:6]2Participants
3
Procedure
By demethylation of 2,3-dihydro-5-methoxy-1H-inden-1-carboxylic acid (IV) with hydrobromic acid at a temperature ranging from 130° C. to boiling temperature of the mixture, 2,3-dihydro-5-hydroxy-1H-inden-1-carboxylic acid (V) was obtained. This acid, by reaction with an aliphatic alcohol in the presence of a sulphonic acid as a catalyzer, led to the corresponding ester. A preferred aliphatic alcohol is methanol. p-Toluensulphonic acid is preferably used as a catalyzer in this esterification. It is convenient that this esterification be carried out at boiling temperature of the mixture. Thus, methyl 2,3-dihydro-5-hydroxy-1H-inden-1-carboxylate (VI) was obtained.
Workup
- customranging from 130° C.