Synthesis of Highly Luminescent Chiral Macrocyclic Molecular Carbon Imides

We report the synthesis of racemic macrocyclic molecular carbon imides, <b>(±)-C[2]BNDI</b> and <b>(±)-C[3]BNDI</b>, using 1,1'-bi(naphthyl-4,5-dicarboximides) (<b>BNDI</b>) as a building block. Single-crystal analysis revealed a twisted saddle-shaped π-framework for <b>(±)-C[2]BNDI</b>. Both macrocycles exhibit strong emission, with <b>(±)-C[2]BNDI</b> showing strong fluorescence (quantum yield = 100%) in nonpolar solvents. After chiral resolution, enantiopure (+)- and (-)-<b>C[2]BNDI</b> is found to exhibit a |<i>g</i>_lum| value of 3.3 × 10^-3 and a high CPL brightness of 63.9 M^-1cm^-1. This study introduces a new class of chiral conjugated macrocycles with outstanding luminescent and chiroptical properties, offering promising opportunities for future applications in photonic and optoelectronic materials.