Diclofenac → S-Diclofenac

Participants

Reaction Conditions

Reaction Steps

To the solution of 1 (diclofenac, 890 mg, 3.0 mmol) in 50 mL of N,N-dimethylformamide, hydroxybenzotriazole (445 mg, 3.3 mmol) and DCC (680 mg, 3.3 mmol) were added with stirring at 0° C. for 1 h. To the reaction mixture 5-p-hydroxyphenyl-1,2-dithiole-3-thione (2; 678 mg, 3 mmol) was added and stirred for 1 h at 0° C. and 3 h at room temperature. After filtration, the filtrate was evaporated under reduced pressure and the oily residue thus obtained was dissolved in ethyl acetate; the organic layer was washed with brine, dried on anhydrous MgSO4, filtered and the solvent evaporated. The crude product 3 was loaded on a silica gel open column and eluted with CH2Cl2/MeOH (9/1), from which [2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid 4-(5-thioxo-5H-[1,2]dithiol-3-yl)-phenyl ester (3) was obtained (1.1 g, 74% yield).

Provenance & Evidence