Sulfuric Acid → 2-[4-(6-Chloro-benzo[b]thiophene-2-sulfonyl)-2-oxo-piperazin-1-ylmethyl]-5,6,7,8-tetrahydro-thiazolo[4,5-c]azepin-4-one

Participants

Reaction Steps

2-[4-(6-Chloro-benzo[b]thiophene-2-sulfonyl)-2-oxo-piperazin-1-ylmethyl]-6,7-dihydro-5H-benzothiazol-4-one (60 mg, 0.12 mmol) is dissolved in CHCl3 (4 mL) and sulfuric acid (0.5 mL) is added with vigorous stirring. Sodium azide (25 mg 0.4 mmol) is added and the reaction is stirred 1¾ h. The reaction is then added dropwise to a rapidly stirring mixture of K2CO3/H20/CH2Cl2. The organic phase is separated and washed with water, dried (MgSO4) and concentrated. The residue is purified by column chromatography (silica, 2% to 6% MeOH/CH2Cl2) to provide a mixture of two products.

Provenance & Evidence