2,3-Dichloronitrobenzene → 6,7-dichloro-1H-indole

Participants

Reaction Conditions

Reaction Steps

800 ml of a 1M solution of vinylmagnesium bromide in THF are cooled to −45° C. under a nitrogen atmosphere, a solution of 51.2 g of 2,3-dichloronitrobenzene in 1000 ml of THF is then added dropwise and the mixture is left stirring at −30° C. for 1 hour. The reaction mixture is poured onto 1000 ml of a saturated NH4Cl solution and extracted with ether, the combined organic phases are washed with water and with a saturated NaCl solution and dried over MgSO4, and the solvents are evaporated under vacuum. The residue is chromatographed on silica gel, elution being carried out with a cyclohexane/EtOAc mixture (95/5; v/v). 27.75 g of the expected compound are obtained.

Provenance & Evidence