Reaction Principles and Crystal Structure Design for the Topochemical Polymerization of 1,3-Dienes

Stacking made to order: Weak intermolecular interactions such as 2D hydrogen-bonding networks, aromatic-ring stacking, and CH/π or halogen–halogen interactions account for the columnar organization of muconic and sorbic acid derivatives in the crystalline state (see picture). When the stacking distance is close to 5 Å these 1,3-dienes undergo topochemical polymerization upon irradiation.