Topochemical Diene and Triene Polymerization

Related to the topochemical diene polymerization is the topochemical triene polymerization. Because dienes successfully undergo a topochemical polymerization with supramolecular structural features similar to topochemical diyne polymerization it would be anticipated that trienes would require similar supramolecular parameters as for triynes. 

This supramolecular structure arises as a result of the isonicotine rings stacking by 71-71 interactions. The question is whether or not this is a persistent supramolecular synthon that can be applied to the polymerization of trienes as well as triynes. Janiak has recently analyzed ti-ti stacking of pyridines [46]. It was observed in the Cambridge Structural Database that a common assembly of pyridines is for them to be oriented in opposite directions with a near-zero angle between the planes of the rings and a close contact distance of 3.57 A (Fig. 5.9). Although there was some 

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