反应详情

To a solution of 2-[3-(tert-butoxycarbonyl-methyl-amino)-prop-1-ynyl]-thiazole-4-carboxylic acid ethyl ester (1.22 g, 3.76 mmol) in THF (10 mL) was added aqueous solution of sodium hydroxide (2 M, 2.82 mL, 5.64 mmol) at RT. After stirring 3 h at RT, the reaction mixture was acidified with 2M aqueous solution of HCl until pH 2, and the solution was extracted with ethylacetate (20 mL). The aqueous layer was re-extracted with ethylacetate (20 mL) and the combined organic layers were washed with brine (10 mL), dried over sodium sulfate, filtered, and evaporated under reduced pressure to 2-[3-(tert-butoxycarbonyl-methyl-amino)-prop-1-ynyl]thiazole-4-carboxylic acid (1.11 g, quant.), which can be used in the next step without further purification. 1H-NMR (400 MHz, d6-DMSO): δ=13.2 (br, 1H), 8.55 (s, 1H), 4.37 (s, 2H), 2.89 (s, 3H), 1.45 (s, 9H). MS: m/z=297 (M+1).

1. extractionthe solution was extracted with ethylacetate (20 mL)
2. extractionThe aqueous layer was re-extracted with ethylacetate (20 mL)
3. washthe combined organic layers were washed with brine (10 mL)
4. dry with materialdried over sodium sulfate
5. filtrationfiltered
6. customevaporated under reduced pressure to 2-[3-(tert-butoxycarbonyl-methyl-amino)-prop-1-ynyl]thiazole-4-carboxylic acid (1.11 g, quant.), which
7. customcan be used in the next step without further purification