SEPARATION OF CONFORMERS .2. AXIAL AND EQUATORIAL ISOMERS OF CHLOROCYCLOHEXANE AND TRIDEUTERIOMETHOXYCYCLOHEXANE

The rate of chair-chair interconversion of cyclohexane derivatives is sufficiently slow at –150° that the conformational isomers may be separated by ordinary recrystallization techniques. Using this method, partial separation of axial and equatorial forms of chlorocyclohexane has been effected. The nmr spectra of pure equatorial chloro- and trideuteriomethoxycyclohexane have been obtained by dissolution of the conformationally pure crystalline materials at –150°. Equatorial cyclohexyl chloride has a half-life of 22 years at –160°, 23 min at -120°, 0.25 sec at -60°, and 10−5 sec at 25°. © 1969, American Chemical Society. All rights reserved.