Acetic Anhydride → 2-Acetoxy-3,5-dichlorobenzoic acid
Reaction equation
[OH:1][C:2]1C(Cl)=CC(Cl)=C[C:3]=1C(N[C@H](C(O)=O)CC1C=CC=CC=1)=O.[Cl:24][C:25]1[CH:33]=[C:32]([Cl:34])[CH:31]=[C:27]([C:28]([OH:30])=[O:29])[C:26]=1[OH:35].C(OC(=O)C)(=O)C>>[C:2]([O:35][C:26]1[C:25]([Cl:24])=[CH:33][C:32]([Cl:34])=[CH:31][C:27]=1[C:28]([OH:30])=[O:29])(=[O:1])[CH3:3]Participants
Procedure
In one non-limiting example of a synthesis method for N-(2-hydroxy-3,5-dichlorobenzoyl)-L-phenylalanine, synthesis begins with reaction of 3,5-dichlorosalicylic acid with acetic anhydride to obtain 2-acetoxy-3,5-dichlorobenzoic acid which in turn is converted into the acid chloride by the action of oxalyl chloride. The 2-acetoxy-3,5-dichlorobenzoic acid chloride is then reacted in situ with phenylalanine ethyl ester hydrochloride, in the presence of triethylamine, to yield ethyl ester of N-(2-acetoxy-3,5-dichlorobenzoyl)-L-phenylalanine. The last step of the synthesis method introduces novel and highly specific hydrolysis of both ester functions of N-(2-acetoxy-3,5-dichloro benzoyl)-L-phenylalanine ethyl ester to obtain the OTA template, N-(2-hydroxy-3,5-dichlorobenzoyl)-L-phenylalanine (I) with 98% yield. This synthesis reaction is summarized in FIG. 2.
Sources & evidence
- ORD record
- ord-c5ce1847f1e34fccbb81e885f53bff2d
- Source dataset
- uspto-grants-2012_04
- Patent number
- US08153737B2
Reaction notes
Loading…