Solid-State Organization Enables Copolymerization

Significance

In this report, Frauenrath and co-workers synthesized symmetric and non-symmetric diacetylenes terminated with phenyl and per­fluorophenyl esters. Although the crystalline diacetylenes did not polymerize when irradiated with UV light, the 1:1 co-crystal gave a poly(diacetylene) copolymer in 35% yield. The authors conclude that the attractive phenyl-perfluoro­phenyl interactions in the co-crystal produce the ideal alignment and spacing between neighboring monomers. The structure of resulting insoluble poly(diacetylene) was confirmed by solid-state CP-MAS ¹³C NMR spectroscopy and Raman spectroscopy. Furthermore, X-ray crystallography on a partially reacted crystal showed a disordered distribution of monomers and the copolymer, providing evidence for the alternating copolymer structure.