A closer look at the gem-CF2 fragment in 15a offers a possible explanation for the lowered susceptibility of the fluorinated oxetane ring towards most chemical reagents studied. While the steric size of the Fluorine atom is relatively low, high Fluorine electronegativity causes the formation of a large negatively charged surface near the potential reaction centers. This, in turn, makes the nucleophilic attack at the oxetane ring less feasible, enhancing the chemical stability of the moiety. The calculated dipole moments of parent cyclobutane 16a and its fluorinated and/or oxygenated analogs 16b-d revealed the higher effect of the gem-CF2 fragment on the overall polarization of 3,3-diFox moiety, which compensated the effect of the Oxygen atom in the oxetane ring (Figure , D). In view of its relatively low dipole moment (0.39 D), the 3,3-diFOx group can be considered as a better mimic of the non-polar cycloalkyl groups than the corresponding simple gem-difluorinated or oxygen-containing counterparts.