Water → 5-(2,6-Dimethylmorpholin-4-yl)isatoic anhydride

Reaction equation

[NH2:1][C:2]1[CH:10]=[CH:9][C:8]([N:11]2[CH2:16][CH:15]([CH3:17])[O:14][CH:13]([CH3:18])[CH2:12]2)=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].O.[O:20]=[C:21](Cl)OC(Cl)(Cl)Cl>O1CCOCC1>[CH3:18][CH:13]1[O:14][CH:15]([CH3:17])[CH2:16][N:11]([C:8]2[CH:7]=[C:3]3[C:4]([O:6][C:21](=[O:20])[NH:1][C:2]3=[CH:10][CH:9]=2)=[O:5])[CH2:12]1

Participants

Procedure

To the mixture of 8.9 g of 2-amino-5-(2,6-dimethylmorpholin-4-yl)benzoic acid in 60 ml of dioxane, under stirring and external cold water cooling 10 ml of diphosgene is added dropwise. The mixture is heated under reflux conditions for 4 hours. From the cold reaction mixture the solid material is filtered off, washed with 50 ml of ether. The product is stirred for 5 minutes in the mixture of 50 ml of methanol and 5 ml of triethylamine, then filtered off and washed with 30 ml of methanol. After drying 7 g of the title product is obtained (MH+: 277).