Synthesis of Pyrrole-Containing Chiral Spiro Molecules and Their Optical and Chiroptical Properties

The pyrrole-containing chiral Spiro pi-conjugated compounds were successfully synthesized from 10,10'-spirobi[indeno-[1,2-b][1]benzothiophene] 5,5-dioxide and 5,5,5',5'-tetraoxide via a sequential inter/intramolecular nucleophilic aromatic substitution with arylamines. The enantiopure ones were also prepared from the enantiopure substrates. UV-vis absorption and photoluminescence spectroscopies and theoretical calculations revealed that the replacement of thiophene unit(s) of 10,10'-spirobi[indeno[1,2-b][1]benzothiophene] with pyrrole unit(s) has a great impact on photophysical properties. The pyrrole-containing chiral spiro pi-conjugated compounds exhibited circularly polarized luminescence with a relatively large dissymmetry factor.