1-Methylpiperazine → 4-[2-(4-Methyl-piperazin-1-yl)-thiazol-4-yl]-benzoic acid

To thiocarbonyldiimidazole (2 g, 11.5 mmol) in THF (30 mL) at RT was added N-methylpiperazine (1.00 g, 10 mmol) drop wise. The reaction was stirred at RT for 2 h and then at 55° C. for 1 h. The reaction was cooled to RT and 20 mL of THF was removed in vacuo. 2M NH3 (10 mL) in MeOH was added and the reaction stirred for 15 h. A further 2M NH3 (10 mL) in MeOH was added and the reaction maintained at 55° C. for 8 h. A pale yellow precipitate (1.00 g) was observed and filtered off, dried and used directly in the next step. The thiourea (0.84 g, 5.2 mmol) was dissolved in EtOH (30 mL) and 4-(2-bromo-acetyl)-benzoic acid (1.28 g, 5.2 mmol) was added. The reaction was heated at reflux for 3 h. The reaction was cooled to RT and the solid filtered off. The solid was washed with Et2O and dried thoroughly. This procedure provided the title compound as a pale yellow solid (1.23 g, 77%).

1. waitat 55° C. for 1 h
2. temperatureThe reaction was cooled to RT
3. custom20 mL of THF was removed in vacuo
4. addition2M NH3 (10 mL) in MeOH was added
5. stirringthe reaction stirred for 15 h
6. additionA further 2M NH3 (10 mL) in MeOH was added
7. temperaturethe reaction maintained at 55° C. for 8 h
8. filtrationfiltered off
9. customdried
10. temperatureThe reaction was heated
11. temperatureat reflux for 3 h
12. temperatureThe reaction was cooled to RT
13. filtrationthe solid filtered off
14. washThe solid was washed with Et2O
15. customdried thoroughly

ORD record

ord-dd0e8557491b49fc842dfb49b5aad7c0

Source dataset

uspto-grants-2011_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07915300B2