Sulfuric acid hydrate (1:1) → 2-Chloro-5-(morpholin-4-ylcarbonyl)-1,3-thiazole-4-carboxylic acid

Participants

Reaction Steps

A solution of 173 mg (1.7 mmol) CrO3 in 1 ml of 4:1 water/H2SO4 was added to as solution of 310 mg (0.82 mmol) of 4-{[4-({[tert-butyl(dimethyl)silyl]oxy}methyl)-2-chloro-1,3-thiazol-5-yl]carbonyl}morpholine (Intermediate 216) in 3 ml acetone cooled in an ice water bath. The mixture was stirred with warming room temperature over 90 min. A few drops of isopropanol were added, and the mixture was diluted with water and extracted 2 times with EtOAc. The EtOAc extracts were washed with brine, dried (MgSO4) and concentrated to give 190 mg of a white solid. MS (ES) (MH+): 277 for C9H9ClN2O4S; NMR (d6-DMSO): 3.3 (m, 4H), 3.6 (m, 4H), 13.7 (s, 1H).

Provenance & Evidence