IN oonnection with studies on the Favorskil rearrangement we have prepared 2-fluorocyclohexanone (I) in 40 per oent yield by reaction of the sodium salt of 2-hydroxymethyleneoyolohexanone with perchloryl fluoride In ethanol. 1 Fluorination is accompanied by loss of the formy group and leads directly to I, b.p. 76-77'/17 mm, g5 -1.4390 (Found8 C, 61.74; H, 7.81; F, 15.96). The oonformation of this simple s-haloketone is of interest since it provides a test for the hypothesisL that conformational equilibria in cyollo a,-haloketones are controlled largely by (1) electrostatic dipole-dipole repulsions which destabilize equatorial halogen, and (2) steric 1,3diaxial interactions, of particular importance in the case of large axial ring substituents, whioh destabilize the exial conformer. Calculation of the eleotrostatic effeat using the mathematical model of Allinger and Allinger Inman, Cesterling end Tyazkowskl, J. Amer. Chem. Soo, SC, 6533 (1958). An independent synthesis of I has been achieved by W. 3: Johnson and V.J. Bauer, University of Wisconsin (Private communication), Corey, J. Amer. Chem. , 2301 (1953). Predominanae of the %hair@@ form is assumed of.paoe Turner, Ibid, a, 4063 (1953)]. Allinger and Allinger, Tetrahedron 2, 64 (1958). The value 1.40 8 for for the C-F bona length snd the ldts 1.40-1.60 for th6 C-F bona moment were employed in the present calculations.