Réaction #7091

Équation de réaction

oxindole

n-butyllithium

1,4-diiodobutane

N,N,N′,N′-tetramethylethylenediamine

→

subtitled compound

Rendement 50.0%

Spiro[cyclopentane-1,3′-[3H]indol]-2′(1′H)-one

Rendement 50.0%

Solvants

THF

water

THF

Conditions de réaction

Traitement

1. 1
   Extractionextracted with EtOAc (×2)
2. 2
   Lavagethe combined organic layers were washed with dil. HCl (pH 1), water (×2)
3. 3
   Séchagedried (MgSO4)
4. 4
   Autreevaporated
5. 5
   AutreThe residue was purified by column chromatography (SiO2, EtOAc: hexane 1:4)

Mode opératoire

To a −25° C. solution of oxindole (2.0 g, 15.0 mmol) in 40 (cm3) of anhydrous THF under N2 was added n-butyllithium (1.6 M in hexanes, 19.7 cm3, 31.5 mmol) drop-wise. To the resulting milky solution was added N,N,N′,N′-tetramethylethylenediamine (4.75 cm3, 31.5 mmol). After 30 min. a solution of 1,4-diiodobutane (21.9 g, 70.6 mmol) in THF (3 cm3) was added and the reaction mixture was allowed to warm to RT and stirred for 14 h. The reaction mixture was poured into water, extracted with EtOAc (×2), then the combined organic layers were washed with dil. HCl (pH 1), water (×2), dried (MgSO4) and evaporated. The residue was purified by column chromatography (SiO2, EtOAc: hexane 1:4) to afford the subtitled compound (1.4 g, 7.5 mmol, 50%) as a tan solid: 1H NMR (CDCl3) δ 1.8–2.2 (m, 8H), 6.94 (dd, J=7.5, 1.0 Hz, 1H), 7.01 (dd, J=7.5, 1.0 Hz, 1H), 7.14–7.25 (m, 2H), 9.30 (br s, 1H).

Source