Unexpected influence of tetra- and pentafluoroethyl groups on the direction of reactions of 2-polyfluoroalkylchromones with 2-aminoethanol

2-Polyfluoroalkylchromones react with 2-aminoethanol at room temperature to give either 3-(2-hydroxyethylamino)-1-(2-hydroxyphenyl)-3-polyfluoroalkylprop-2-en-1-ones [R^F = CF₂H, CF₃, (CF₂)₂OCF₃ or (CF₂)₃CF₃] or N-(2-hydroxyethyl)-2-polyfluoroalkyl-4H-chromene-4-imines [R^F = (CF₂)₂H or C₂F₅].