Réaction #9407

Équation de réaction

1,5-diiodopentane

oxindole

n-butyllithium

ammonium chloride

N,N,N′,N′-tetramethylethylenediamine

→

subtitled compound

Rendement 69.6%

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

Rendement 69.6%

Solvants

tetrahydrofuran

EtOAc

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONwere added
2. 2
   workup.WAITAfter 15 min.
3. 3
   Autrethe layers were separated
4. 4
   Extractionthe aqueous phase was extracted with EtOAc (×2)
5. 5
   ExtractionThe combined organic layers were extracted with hydrochloric acid (1N)
6. 6
   Lavagewashed with brine (500 cm3)
7. 7
   Séchagedried (MgSO4)
8. 8
   Concentrationconcentrated
9. 9
   Autreto obtain an oil
10. 10
    AutreThe oil was triturated with hexane (200 cm3) and benzene (20 cm3)
11. 11
    AutreThe precipitate was collected
12. 12
    Autredried in vacuo

Mode opératoire

A solution of oxindole (25 g, 0.19 mol) in anhydrous tetrahydrofuran (800 cm3) was cooled to −20° C., then n-butyllithium (2.5M in hexanes, 152 cm3, 0.38 mol) was added slowly followed by N,N,N′,N′-tetramethylethylenediamine (51 cm3, 0.38 mol,). After 15 min. 1,5-diiodopentane (174 g, 0.54 mol) was added slowly and the mixture was allowed to warm to room temperature. After stirring for 16 h. saturated aqueous ammonium chloride solution (1 L) and EtOAc (1 L) were added. After 15 min., the layers were separated and the aqueous phase was extracted with EtOAc (×2). The combined organic layers were extracted with hydrochloric acid (1N), then washed with brine (500 cm3), dried (MgSO4), and concentrated to obtain an oil. The oil was triturated with hexane (200 cm3) and benzene (20 cm3). The precipitate was collected and dried in vacuo to obtain the subtitled compound (26.3 g, 69.6%) as colorless crystals: mp 110–114° C.; 1H NMR (DMSO-d6) δ 1.67 (m, 10H), 6.84 (d, 1H, J=8 Hz), 6.94 (t, 1H, J=8 Hz), 7.17 (t, 1H, J=8 Hz), 7.44 (d, 1H, J=8 Hz), 10.3 (s, 1H).

Source