Acetic Acid → 2-Amino-6-methylbenzothiazole

Temperatur

80 °C

(4-Methylphenyl)thiourea (2 mmol) was added to AcOH (4 ml), and the suspension was heated to 80° C. To the solution formed was added 33% HBr in AcOH (4 mmol) followed by DMSO (2.1 mmol). After stirring at 80° C. for 1 h, the reaction mixture was cooled to 50° C., diluted with EtOAc (10 ml) and filtered. The product (as HBr-salt) was taken up in H2O (5 ml) and treated with 1M aq. NaHCO3 (2 ml). Stirring was continued for 0.2 h. The precipitated aminobenzothiazole was then filtered, washed with H2O (10 ml) and dried (16 h at 45° C./20 mb); yield 67%.

1. customTo the solution formed
2. temperaturethe reaction mixture was cooled to 50° C.
3. filtrationfiltered
4. additiontreated with 1M aq. NaHCO3 (2 ml)
5. stirringStirring
6. waitwas continued for 0.2 h
7. filtrationThe precipitated aminobenzothiazole was then filtered
8. washwashed with H2O (10 ml)
9. customdried (16 h at 45° C./20 mb)

ORD-Eintrag

ord-2c38c04a2ff54f61871a1c6ab0095848

Quelldatensatz

uspto-grants-2006_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07087761B2