Fig. 6: Unsuccessful attempt to realize the multicomponent reaction to generate α,α-difluorinated O-heterocycles predicted by AFIR.

a, The energy barriers for the formation of A5–A7 obtained in the calculations shown in Figs. 2 and 3. b, Experimental investigations with 3a and 3c, and their energy barriers for the cycloaddition obtained by optimizing the transition-state geometries at the ωB97X-D/Def2-SVP/CPCM(THF) level of theory.