Stability of Cycloalkene ring connects CH CH,H CH,-CH2 behind the double bond. CH: CH: CH. CH. CH, H CH2 H CH, H CH2 CH,-CH, trans cyclic system trans-cycloheptene trans-cyclooctene cis-cyclooctene marginally stable stable more stable Copyright 2010 Pearson Prentice Hall,Inc. Cis isomer more stable Small rings have additional ring strain. Must have at least eight carbons to form a stable trans double bond. For cyclodecene (and larger),the trans double bond is almost as stable as the cis.Stability of Cycloalkene ❖Cis isomer more stable ❖Small rings have additional ring strain. ❖Must have at least eight carbons to form a stable trans double bond. ❖For cyclodecene (and larger), the trans double bond is almost as stable as the cis