F2ClC−CClF2\mathrm{F}_{2} \mathrm{ClC}-\mathrm{CClF}_{2}F2ClC−CClF2
C6H5−CN\mathrm{C}_{6} \mathrm{H}_{5}-\mathrm{CN}C6H5−CN
CCl3−NO2\mathrm{CCl}_{3}-\mathrm{NO}_{2}CCl3−NO2
(CH3)3C−OH\left(\mathrm{CH}_{3}\right)_{3} \mathrm{C}-\mathrm{OH}(CH3)3C−OH