Water → Ethyl 2-(2-aminothiazol-5-ylthio)acetate

Temperature

0 °C

5-Bromo-2-aminothiazole (25 g, 96 mmol) and K2CO3 (26.5 g, 192 mmol) was suspended in DMF (50 mL) and stirred at 0° C. Ethyl thioglycolate (11.6 mL, 96 mmol) was added over 10 min. The reaction mixture was allowed to reach room temperature and stirred for a further 13 h. The mixture was divided between H2O (100 mL) and EtOAc (150 mL). Separation of the organic phase followed by extraction of the aqueous phase with EtOAc (2×100 mL).The combined organic phases were washed with aqueous NaHCO3 (2000 mL), brine (2×200 mL) and dried (MgSO4), filtered and evaporated. The crude product was dissolved in a small amount of DCM and purified by flash chromathography (SiO2, 2% TEA in EtOAc-heptane, from 30%→100%) to give 50-65% pure (2-aminothiazol-5-ylsulfanyl) acetic acid ethyl ester as a dark red-brown oil.

1. customto reach room temperature
2. stirringstirred for a further 13 h
3. customSeparation of the organic phase
4. extractionfollowed by extraction of the aqueous phase with EtOAc (2×100 mL).The combined organic phases
5. washwere washed with aqueous NaHCO3 (2000 mL), brine (2×200 mL)
6. dry with materialdried (MgSO4)
7. filtrationfiltered
8. customevaporated
9. dissolutionThe crude product was dissolved in a small amount of DCM
10. custompurified by flash chromathography (SiO2, 2% TEA in EtOAc-heptane, from 30%→100%)

ORD record

ord-7a66f0e8a94c4e4099490dee60072fc7

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08318778B2