2-Aminothiophenol → ethyl (2E)-2H-1,4-benzothiazin-3(4H)-ylideneethanoate

Participants

Reaction Steps

step 1—To a solution of 2-aminothiophenol (4.96 g, 39.6 mmol) in MeOH (200 mL) was added the ethyl 4-chloroacetoacetate (6.2 g, 38 mmol). After stirring at room temperature for 2 h the MeOH was removed under reduced pressure. The residue was dissolved in Et2O and washed with HCl (1N), saturated NaHCO3, and brine. The organic phase was dried over MgSO4, filtered and the solvent was removed under reduced pressure. The product was obtained from a minimum of EtOH to afford 5.0 g (54%) of 8: LCMS RT 3.7 min, M+H.

Provenance & Evidence