反应详情

A mixture of 5-bromo-3-[(2,2-dimethyl-[1,3]dioxan-5-yl)-(trans-4-methyl-cyclohexanecarbonyl)-amino]-thiophene-2-carboxylic acid methyl ester (35 mg) contaminated with a small impurity in THF (1.1 mL) and 3N HCl (0.75 mL) was stirred at room temperature for 16 h. It was neutralized with solid NaHCO3 and evaporated down to dryness. The residue was triturated with ethyl acetate (3×8 mL). The ethyl acetate extracts were combined, evaporated and chromatographed over silica gel (hexane:EtOAc—1:1) yielding pure 5-bromo-3-[(2-hydroxy-1-hydroxymethyl-ethyl)-(trans-4-methyl-cyclohexanecarbonyl)-amino]-thiophene-2-carboxylic acid methyl ester (18 mg; 7.2% in two steps).

1. customevaporated down to dryness
2. customThe residue was triturated with ethyl acetate (3×8 mL)
3. customevaporated
4. customchromatographed over silica gel (hexane:EtOAc—1:1)