反应详情

Methyl 4H-thieno[3,2-b]pyrrole-5-carboxylate (2.8 g, 15.45 mmol) was dissolved in 150 mL anhydrous THF. NaH (3.0 g, 60% oil dispersion, 75 mmol) was added and the reaction stirred for 15 min at rt. SEMCl [(2-trimethylsilyl)-ethoxymethyl chloride] (0.7 mL, 3.95 mmol) was added dropwise over 5 min. The reaction was stirred 1 h at rt and then CAUTIOUSLY poured onto 25 g crushed ice with stirring. The aqueous was extracted with EtOAc, dried (Na2SO4), filtered and evaporated in vacuo to give a green residue. The residue was chromatographed over silica gel (EtOAc in heptane, 3%-10%, 3 h, TLC visualized with KMnO4 with heat) to give methyl 4-(2-trimethylsilanyl-ethoxymethyl)-4H-thieno[3,2-b]pyrrole-5-carboxylate (3.85 g, 80% yield). 1H NMR (400 MHz, (CD3)2CO) δ ppm −0.08 (s, 9H) 0.84 (t, J=7.83 Hz, 2H) 3.54 (t, J=7.88 Hz, 2H) 3.83 (s, 3H) 5.94 (s, 2H) 7.21-7.25 (m, 1H) 7.26 (s, 1H) 7.55 (d, J=5.37 Hz, 1H).

1. stirringThe reaction was stirred 1 h at rt
2. additionCAUTIOUSLY poured onto 25 g
3. customcrushed ice
4. stirringwith stirring
5. extractionThe aqueous was extracted with EtOAc
6. dry with materialdried (Na2SO4)
7. filtrationfiltered
8. customevaporated in vacuo
9. customto give a green residue
10. customThe residue was chromatographed over silica gel (EtOAc in heptane, 3%-10%, 3 h, TLC visualized with KMnO4 with heat)