The structure and attempted topochemical polymerization of single crystalline 1, 1, 4, 4-bis(pentamethylene)-1, 2, 3-butatriene

摘要

The photo-initiated solid-state topochemnical polymerization of 1, 1, 4, 4-bis(pentamethylene)-1, 2, 3-butatriene (1) was attempted unsuccessfully. Since 1 readily polymerizes in the liquid state, a structural study was undertaken to better understand its inertness in the solid-state. 1 crystallizes in the monoclinic space group P2_1 with a = 6.4597(6), b = 10.8914 (10), c = 8.4396(8) A, #beta# = 100.168(2) deg, V = 584.44(9) A~3, and Z = 2. The crystal structure reveals that while the alignment of the #pi#-systems in the solid-state is acceptable for supporting the targeted polymerization reaction, the reaction centers are located too far apart to allow the reaction to take place. Additionally, comparison of the molecular structure of 1 with the limited number of other structurally characterized butatrienes has provided insight into the steric and electronic influences played by the substituents attached to the cumulene moiety.