Reaktion #2266585

Reaktionsgleichung

product

2-tert-butyl 1-ethyl-6-chloro-8-(phenylsulfonyl)-3,4-dihydrobenzofuro[3,2-c]pyridine-1,2(1H)-dicarboxylate

HCl

dichloromethane

sodium bicarbonate

→

ethyl 6-chloro-8-(phenylsulfonyl)-1,2,3,4-tetrahydrobenzofuro[3,2-c]pyridine-1-carboxylate

Ausbeute 99.0%

Lösungsmittel

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvents were removed in vacuo
2. 2
   Sonstigeto afford a brown residue which
3. 3
   ExtraktionThe resulting solution was extracted with ethyl acetate (3×15 mL)
4. 4
   TrocknenThe combined organic extracts were dried over anhydrous Na2SO4
5. 5
   Filtrationfiltered
6. 6
   Einengenthe filtrate was concentrated in vacuo
7. 7
   SonstigeThe residue was purified by flash column chromatography (SiO2, 4:2 to 3:7, hexanes/ethyl acetate)

Vorschrift

To a stirred solution of the product of step C (60 mg, 0.12 mmol) in dichloromethane (2 mL) was added 4M HCl in dioxane (2 mL). The resulting solution was stirred at ambient temperature for 3 h. The solvents were removed in vacuo to afford a brown residue which was treated with saturated aqueous sodium bicarbonate (15 mL). The resulting solution was extracted with ethyl acetate (3×15 mL). The combined organic extracts were dried over anhydrous Na2SO4, filtered and the filtrate was concentrated in vacuo. The residue was purified by flash column chromatography (SiO2, 4:2 to 3:7, hexanes/ethyl acetate) to afford ethyl 6-chloro-8-(phenylsulfonyl)-1,2,3,4-tetrahydrobenzofuro[3,2-c]pyridine-1-carboxylate (51 mg, 99%) as a brown oil: 1H NMR (CDCl3, 300 MHz) δ 8.23 (d, J=1.8 Hz, 1H), 7.97-7.85 (m, 2H), 7.70-7.57 (m, 4H), 4.76 (s, 1H), 4.27-4.17 (m, 2H), 3.77-3.63 (m, 2H), 3.42-3.22 (m, 1H), 2.98-2.76 (m, 1H), 1.28 (t, J=7.2 Hz, 3H).

Quelle