Difluorotris(pentafluoroethyl)phosphorane—A highly active catalyst for Diels–Alder reaction

•Difluorotris(pentafluoroethyl)phosphorane, (C2F5)3PF2, easy to handle non-metal based strong Lewis acid.•(C2F5)3PF2 efficiently catalyzes Diels–Alder reactions under mild conditions.•The products of Diels–Alder reaction catalyzed by difluorotris(pentafluoroethyl)-phosphorane, (C2F5)3PF2, are isolated in high to moderate yields.

Difluorotris(pentafluoroethyl)phosphorane, (C2F5)3PF2, was found to catalyze Diels–Alder reactions of α,β-unsaturated ketones or aldehydes with conjugated dienes or cyclodienes providing the cycloaddition products in high yields. Only a small quantity of this catalyst is required to complete the Diels–Alder reaction. The developed protocol is more convenient than the procedures reported in the literature. Several cyclohexene, naphthalene and norbornene derivatives were obtained in moderate to good yields.

Graphical abstractDifluorotris(pentafluoroethyl)phosphorane, (C2F5)3PF2, is easy to handle non-metal based strong Lewis acid that efficiently catalyzes Diels–Alder reactions under mild conditions.Figure optionsDownload full-size imageDownload as PowerPoint slide