Controlled Synthesis of Cyclopenta-Fused B2N2-Pyrene and Diazaborepin:
Structures and Optical Properties
Abstract
Cyclopenta-fused B2N2-pyrene (B2N2CP) and diazaborepin (NBNM) have been
accomplished from a same bi-indoles pre-cursor in three steps.
Borylative cyclization of bi-indoles precursor with 2.0 equiva-lents
BCl3 afforded NBNM as the major product, whereas increasing the BCl3 to
3.0 equivalents deliv-ered B2N2CP as the major product. Both B2N2CP and
NBNM are highly emissive in solution. B2N2CP emit in deep blue region,
while NBNM emit in the region of blue to green. Moreover, we found that
flu-oride anion addition to the solution of B2N2CP and NBNM led to great
change of their absorption and emission spectra.