Polydiacetylenes with Long Wavelength Absorption

A series of 1,6-disubstituted-2,4-hexadiynes, where the substituents are para-substituted benzene rings that have either a dicyanovinyl or tricyanovinyl group as one substituent and have either an oxygen or N-alkyl group connecting to the hexadiyne chain, was designed to lead to polydiacetylenes (PDAs) with long wavelength absorption, and these PDAs were synthesized. These new compounds, in contrast to other diacetylene monomers, are relatively insensitive to ultraviolet light and ionizing radiation under ambient temperature and require heating above 100 °C to bring about preparatively useful conversion to polymer. The new PDAs have the usual en-yne backbone structure as shown by Raman spectroscopy. Three of the new PDAs exhibit maxima in diffuse reflectance at wavelengths as long as or longer than the PDA of 1,6-di-N-carbazolyl-2,4-hexadiyne.