Bimane Acetylenes and Diacetylenes. Bimanes. 33

Two series (4,6-dihydro and 4,6-dimethyl) of syn-bimanes [1,5-diazabicyclo[3.3.0]octa-3,6-diene-2,8-diones] have been converted to acetylene and diacetylene derivatives. Their chemical and photophysical properties are reported. The 3-(and 6-)iodo (diiodo) derivatives are the best choices for Stille or Heck condensations with acetylenes or acrylates. Desilylation of (trimethylsilyl)acetylenes is best carried out with silver nitrate followed by lithium bromide. The acetylenes and diacetylenes are quite stable and highly fluorescent and represent candidate units for incorporation into polymers.