Tributylstannane → 7-Chloro-2,3-dihydro-1H-pyrrolo[1,2-a]indole-9-carboxaldehyde

Participants

Reaction Steps

To a stirred solution of 5-chloro-1-(3-iodopropyl)indole-3-carboxaldehyde (5.0 g, 14 mmol) in toluene (75 mL) at reflux under argon was added dropwise over 2 h a solution of 1,1′-azobis(cyclohexanecarbonitrile) (3.5 g, 14 mmol) and tri-n-butyltin hydride (7.8 mL, 29 mmol) in toluene (75 mL). The mixture was stirred for 3 h, cooled to room temperature, and potassiurn fluoride (3.5 g, 60 mmol) and water (15 mL) were added. The mixture was stirred for 18 h and filtered through a pad of kieselguhr. The filter-cake was washed (ethyl acetate) and the filtrate was concentrated in vacuo, purified by colurnn chromatography [SiO2; ethyl acetate-hexane (9:1)] and recrystallised (methanol) to give the product as a white solid (1.1 g, 36%): mp 179-180° C.; Found: C, 65.54; H, 4.61; N, 6.38%. C12H10ClNO requires: C, 65.61; H, 4.59; N, 6.37%.

Provenance & Evidence