Trifluoroacetic acid → 2-({4-[2-(9H-fluorene-9-ylmethoxy)-2-oxoethyl]-1,3-thiazol-2-yl}thio)-2-methylpropionic acid

Participants

Reaction Steps

To a solution of 2-({4-[2-(9H-fluorene-9-ylmethoxy)-2-oxoethyl]-1,3-thiazol-2-yl}thio)-2-methylpropionic acid tert-butyl ester (260 g) obtained in Example 461-1 in dichloromethane (400 mL) was added trifluoroacetic acid (100 mL), and the mixture was stirred at room temperature overnight and heated at 45° C. with stirring for 8 hr. The reaction mixture was concentrated, ethyl acetate was added, and the organic layer was washed with saturated brine and dried over sodium sulfate. The solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel chromatography (elution solvent; hexane:ethyl acetate=1:1) to give the title compound (250 g) as a yellow oil.

Provenance & Evidence