Hydrochloric Acid → Piroxicam

Reaktionsgleichung

[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH:7][C:8]([C:10]1[N:11]([CH3:31])[S:12](=[O:30])(=[O:29])[C:13]2[CH:28]=[CH:27][CH:26]=[CH:25][C:14]=2[C:15]=1S(C1C=CC=CC=1)(=O)=O)=[O:9].Cl.[OH2:33]>>[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH:7][C:8]([C:10]1[N:11]([CH3:31])[S:12](=[O:30])(=[O:29])[C:13]2[CH:28]=[CH:27][CH:26]=[CH:25][C:14]=2[C:15]=1[OH:33])=[O:9]

Komponenten

Edukt 3

HCID 313Hydrochloric Acid

HCID 962Water

HCID 20191277N-(2-pyridyl)-4-(benzenesulfonyl)-2-methyl-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide

Produkt 1

HCID 54676228PiroxicamAusbeute 91,1 %

Versuchsvorschrift

2.36 g (0.005 mole) N-(2-pyridyl)-4-(benzenesulfonyl)-2-methyl-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide was dissolved in 50 ml water containing 1.0 g sodium hydroxide. After it was completely hydrolysed, the solution was neutralized with conc-hydrochloric acid to form precipitates. The obtained precipitates were filtered and recrystalized with methanol and N,N-dimethyl formamide and n-hexane to obtain 1.51 g of the title compound. Yield: 91%. m.p. 198°-201° C.