Penta- and Decafluorinated Dibenzalacetones: Synthesis, Crystal Structure, and Cocrystallization Experiments

The nonfluorinated parent dibenzalacetone 1 as well as the corresponding penta- (2) and decafluorinated (3) derivative compounds were prepared, crystallized, and subjected to co-crystallization experiments. Only 3 yielded a 1:1 co-crystal with 1, while 2 did not form co-crystals with either 1 or 3. Powder X-ray diffraction patterns were determined to verify the co-crystallization experiments. The influence of the fluorine on the molecular geometry and crystal packing were studied and comparatively discussed. Conclusions with reference to the priority of Ar···ArF contact modes in the crystalline packing being in competition with other fluorine and non-fluorine involved supramolecular interactions were drawn.