1-(2-Hydroxyethyl)piperazine → 1-(Thiophen-2-yl)piperazine

Participants

Reaction Steps

2-[1-(2'-hydroxyethyl)piperazino] thiophene 18 was prepared by warming a solution containing thiophene-2-thiol (1.16 g, 10.0 mmol.) and 1-(2-hydroxyethyl) piperazine (1.43 g, 11.0 mmol.) in toluene to reflux under an argon atmosphere for two hours. Completion of the reaction was confirmed by thin layer chromatography using a 4:1 ratio blend of hexane and ethyl acetate as the eluent. The reaction mixture was cooled to room temperature, and the solvent was removed in vacuo. The residue was then concentrated onto 5 g of silica. The silica was added to a medium pressure chromatography column packed with silica. The column was eluted with a 4:1 ratio blend of hexane and ethyl acetate to yield the pure piperazino-thiophene 18 (1.62 g, 76.4% yield) as a pale yellow solid.

Provenance & Evidence