反应详情

A suspension of methyl hydroxy(4-iodo-2-methyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-b]pyridin-3-yl)acetate (Preparation 9, 10.0 g, 23.97 mmol) in tert-butyl acetate (250 mL) was stirred vigorously for 5 minutes prior to the dropwise addition of perchloric acid (70%, 6.15 mL, 71.90 mmol). The resulting mixture was stirred at room temperature for 20 minutes. The mixture was neutralised by addition of a saturated aqueous sodium hydrogen carbonate solution (60 mL) and extracted with ethyl acetate (250 mL). The layers were separated and the aqueous layer was further extracted with ethyl acetate (250 mL). The combined organic layers were washed with brine (250 mL), dried over MgSO4 and concentrated in vacuo to yield the crude product. The residue was purified by flash column chromatography eluting with ethyl acetate/heptane (10-40%) to give the title compound, 4.26 g, in a 38% yield. 1H NMR (400 MHz, CDCl3) δ ppm 1.23 (s, 9H), 1.81-1.92 (m, 4H), 2.66 (s, 3H), 2.79-2.89 (m, 2H), 3.21-3.27 (m, 2H), 3.68 (s, 3H), 5.95 (s, 1H).

1. stirringThe resulting mixture was stirred at room temperature for 20 minutes
2. extractionextracted with ethyl acetate (250 mL)
3. customThe layers were separated
4. extractionthe aqueous layer was further extracted with ethyl acetate (250 mL)
5. washThe combined organic layers were washed with brine (250 mL)
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo
8. customto yield the crude product
9. customThe residue was purified by flash column chromatography
10. washeluting with ethyl acetate/heptane (10-40%)