2-(5-Nitro-2-pyridinylthio)ethyl-3-chlorobenzoate → 2-[(5-Amino-2-pyridinyl)thio]ethyl-3-chlorobenzoate

Reaction equation

[N+:1]([C:4]1[CH:5]=[CH:6][C:7]([S:10][CH2:11][CH2:12][O:13][C:14](=[O:22])[C:15]2[CH:20]=[CH:19][CH:18]=[C:17]([Cl:21])[CH:16]=2)=[N:8][CH:9]=1)([O-])=O>C1(C)C=CC=CC=1.CO.[Pd]>[NH2:1][C:4]1[CH:5]=[CH:6][C:7]([S:10][CH2:11][CH2:12][O:13][C:14](=[O:22])[C:15]2[CH:20]=[CH:19][CH:18]=[C:17]([Cl:21])[CH:16]=2)=[N:8][CH:9]=1

Participants

Procedure

A mixture of 2-[(5-nitro-2-pyridinyl)thio]ethyl 3-chlorobenzoate (5) (0.24 g, 0.71 mmol) and 10% Pd/C (0.10 g) in toluene or methanol was agitated under a hydrogen atmosphere (40 PSI) for 1 h. The reaction mixture was filtered through Celite® and concentrated to give 2-[(5-amino-2-pyridinyl)thio]ethyl-3-chlorobenzoate (51), LCMS: purity: 99%; MS (m/e): 309 (MH+), which was used without further purification. Acetyl chloride (4.6 μL, 0.064 mmol) was added to a room temperature solution of 2-[(5-amino-2-pyridinyl)thio]ethyl-3-chlorobenzoate (51) (18.9 mg, 0.061 mmol) and triethylamine (18 μL, 0.13 mmol) in anhydrous dichloromethane (1.0 mL), After 16 h, the reaction mixture was diluted with dichloromethane and washed with 1N HCl and brine and then dried over anhydrous MgSO4. Purification by silica gel chromatography provided 2-[(5-acetylamino-2-pyridinyl)thio]ethyl-3-chlorobenzoate (52), LCMS: purity: 99%; MS (m/e): 351 (MH+).