Influence of Extended Conjugation on Photophysical/Electronic Properties and Photoelimination of BN-Heterocycles

A 1,1-hydroboration reaction was
used successfully to create brominated
BN-heterocyclic compounds, which are amenable to Stille coupling reactions
for the construction of new BN-heterocyclic compounds, including a
new polymeric BN-heterocycle that has an extended π-conjugated
backbone. The conjugated backbone of the new BN-heterocycles was found
to have a great influence on the photophysical and electronic properties
of this class of compounds. In addition, the photoelimination reactivity
of the new BN-heterocycles was also found to be greatly dependent
on the extent of the conjugated backbone. Several new 1,2,4-triazole-fused
boranaphthalenes have been obtained successfully via photoelimination.