Substituent Effects Among constitutional isomers,more substituted double bonds are usually more stable.Wider separation between the groups means less steric interaction and increased stability. less substituted more substituted H 109.5° H3C separation H3 .tl 120° H separation CH3 closer groups wider separation Copyright 2010 Pearson Prentice Hall,Inc.Substituent Effects Among constitutional isomers, more substituted double bonds are usually more stable. Wider separation between the groups means less steric interaction and increased stability