Reaktion #77333

Reaktionsgleichung

5-bromoindole-2-carboxylic acid ethyl ester

tert-butyl acrylate

triethylamine

water

→

5-(2-tert-butoxycarbonyl-vinyl)-1H-indole-2-carboxylic acid ethyl ester

Ausbeute 28.5%

Lösungsmittel

acetic acid

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe cooled reaction mixture
2. 2
   FiltrationThe biphasic mixture was filtered through a pad of celite
3. 3
   Extraktionthe aqueous layer was extracted with dichloromethane (2×)
4. 4
   WaschenThe combined organic layers were washed with saturated sodium bicarbonate solution, brine
5. 5
   Sonstigedried
6. 6
   Einengenconcentrated
7. 7
   SonstigeThe residue was purified by column chromatography (10% of ethyl acetate in hexanes)

Vorschrift

A mixture of 5-bromoindole-2-carboxylic acid ethyl ester (2.68 g, 10 mmol), tert-butyl acrylate (4.4 mL, 30 mmol) and dichlorobis(triphenylphosphine)palladium(II) (0.7 g, 1 mmol) and triethylamine (17 mL) in acetic acid (17 mL) was heated at 120° C. in a closed vessel for 6 hrs. The cooled reaction mixture was poured into water and dichloromethane. The biphasic mixture was filtered through a pad of celite and the aqueous layer was extracted with dichloromethane (2×). The combined organic layers were washed with saturated sodium bicarbonate solution, brine, dried and concentrated. The residue was purified by column chromatography (10% of ethyl acetate in hexanes) to give 900 mg (28%) of 5-(2-tert-butoxycarbonyl-vinyl)-1H-indole-2-carboxylic acid ethyl ester.

Quelle