2,4-Dichloro-5-(chlorosulphonyl)benzoic acid → 4-Methyl-5-methylsulfonylanthranilic acid
Reaction equation
Cl[C:2]1C=C(Cl)C(S(Cl)(=O)=O)=CC=1C(O)=O.[CH3:16][C:17]1[CH:18]=[C:19]([NH2:30])[C:20](=[CH:24][C:25]=1[S:26](Cl)(=[O:28])=[O:27])[C:21]([OH:23])=[O:22]>>[CH3:16][C:17]1[CH:18]=[C:19]([NH2:30])[C:20](=[CH:24][C:25]=1[S:26]([CH3:2])(=[O:28])=[O:27])[C:21]([OH:23])=[O:22]Participants
Procedure
This product is prepared by replacing the 2,4-dichloro-5-chlorosulfonylbenzoic acid employed in Example 1, Step A, by an equimolecular proportion of 4-methyl-5-chlorosulfonylanthranilic acid and then following substantially the same procedure described in Example 1, Steps A and B, there is obtained 4-methyl-5-methylsulfonylanthranilic acid employed in the following step without purification. The compound thus obtained is combined with excess furfural and heated on a water bath at about 80° C. The water formed during the reaction is removed by azeotropic distillation with the excess furfural at about 15 mm. Hg. pressure over a one hour period. The 2-furfurylideneamino-4-methyl-5-methylsulfonylbenzoic acid formed is stirred while cooling in acetic acid while a mixture of trimethylamine-borane complex in acetic acid is added over a 10 minute period. The reaction mixture then is heated on the steam bath for 5-10 minutes, then quenched in ice water to give 2-furfurylamino-4-methyl-5-methylsulfonylbenzoic acid.
Workup
- customThis product is prepared
Sources & evidence
- ORD record
- ord-017ba53864b949b7905ebbf2184e7e51
- Source dataset
- uspto-grants-1976_04
- Patent number
- US03953476
Reaction notes
Loading…