Fluorene-2-carboxaldehyde → 2-ethenyl-9H-fluorene

Participants

Reaction Steps

Triphenylmethyl phosphonium bromide (36 gms/0.1 mole) in 500 milliliters of dry THF is treated under nitrogen with 90 milliliters of a 1.1 molar solution of n-butyl lithium in hexane and stirred for 2 hours. A solution of 19.4 gms. (0.1 mole) of fluorene-2-carboxaldehyde in 100 milliliters of THF is added dropwise and the final mixture refluxed for 1 1/2 hours. One liter of hexane is added to the cold solution and the precipitate filtered off. The filtrate is evaporated and the residue chromatographed on alumina (Woehlm neutral) using hexane to give 15 gms. (75% theory) of product. Recrystallization from hexane yields 2-vinylfluorene as colorless plates. The structure of the product is confirmed by nuclear magnetic resonance and elemental analysis.

Provenance & Evidence