3-Furaldehyde → (E)-3-styrylfuran

Participants

Reaction Steps

Potassium tert-butoxide (35.7 g) was added in one portion to a stirred suspension of benzyltriphenylphosphonium chloride (41.6 g) in ether (1 liter). After 1 hour, a solution of 3-formylfuran (17.5 g) in ether (60 ml) was added to the resulting orange mixture which was then stirred for 2 hours, poured into water, and extracted with ether. The extracts were washed with water, dried and concentrated to give a solid. Trituration of this solid with ether enabled much of the weakly-soluble triphenylphosphine oxide and excess phosphonium salt to be separated, and the ether-soluble fraction (37.06 g) was chromatographed using ether as eluent to give a mixture of (E)- and (Z)-isomers of 3-styrylfuran (27 g) as a yellow solid. Crystallisation twice from methanol gave (E)-3-styrylfuran (5.12 g), mp 96° C., as a yellow solid.

Provenance & Evidence