N,N,N',N'-Tetramethylethylenediamine → 6'-Bromospiro[cyclopentane-1,3'-indolin]-2'-one

Temperatur

-20 °C

n-Butyl lithium (2.5 M in hexanes, 3.8 mL, 9.5 mmol) was added dropwise over 30 minutes to a stirred suspension of 6-bromoindolin-2-one (preparation 1, 1.00 g, 4.7 mmol) and N,N,N′,N′-tetramethylethylenediamine (1.42 mL, 9.4 mmol) in tetrahydrofuran (20 mL) at −78° C. The mixture was stirred for 1 hour, then 1,4-diiodobutane (3.11 mL, 23.6 mmol) was added dropwise over 5 minutes. The mixture was warmed to −20° C. over a 1 hour period, was stirred for a further hour at this temperature and was then warmed to room temperature. After 3 hours stirring at room temperature, saturated aqueous ammonium chloride solution was added to the reaction and the mixture was extracted with ethyl acetate. The organic layer was washed with water, brine, dried (MgSO4) and evaporated. Purification of the residue by flash chromatography (10:1 hexanes/ethyl acetate) gave the title compound (0.57 g, 45%) as a pale pink solid.

1. stirringwas stirred for a further hour at this temperature
2. temperaturewas then warmed to room temperature
3. stirringAfter 3 hours stirring at room temperature
4. extractionthe mixture was extracted with ethyl acetate
5. washThe organic layer was washed with water, brine
6. dry with materialdried (MgSO4)
7. customevaporated
8. customPurification of the residue by flash chromatography (10:1 hexanes/ethyl acetate)

ORD-Eintrag

ord-f6b086492ca44bd5bd1fbd33eea48b0c

Quelldatensatz

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08772288B2