Dicyclohexylcarbodiimide → HCID 11976036, compound

Participants

Reaction Conditions

Reaction Steps

To the solution of 4- or 5-tert-butoxycarbonylamino-2-hydroxy-benzoic acid (2) (3.0 mmol) in 50 mL of dimethylformamide, hydroxybenzotriazole (3.3 mmol) and DCC (3.3 mmol) were added with stirring at 0° C. for 1 h. To the reaction mixture, 4-hydroxy-thiobenzamide (3.0 mmol) was added and stirred mechanically for 3 h at 0°C. and 72 h at room temperature. After filtration, the filtrate was evaporated under reduced pressure to remove the solvent. The oily residue thus obtained was dissolved in ethyl acetate; the organic layer washed with brine, dried on anhydrous MgSO4, filtered and the solvent evaporated. The crude intermediate (7) was treated with a solution of 40% TFA in CH2Cl2. After 2 h the solvent was removed to obtain compound (8) as a crude residue. The residue was loaded on a silica gel open column and eluted with CH2Cl21MeOH (8/2), from which 4- or 5-Amino-2-hydroxy-benzoic acid 4-thiocarbamoyl-phenyl ester (8), compound of Formula XXVII, was obtained (48% yield).

Provenance & Evidence