Fig. 2. Symmetry-breaking assembly consisting of resorcin[4]arene and cationic Ir complex.

a Schematic representation of the assembly. ¹H NMR spectra (500 MHz, CDCl₃, RT) of b resorcin[4]arene hexameric capsule (1a)₆, c Ir complex [2a]Cl, d a mixture of (1a)₆ and [2a]Cl, e the mixture after heating at 50 °C for 1 h, and f partial ¹H DOSY spectrum of the host–guest complex showing the diffusion coefficient (D) around 3.6 ± 0.4 × 10⁻¹⁰ m² s⁻¹. The signals marked with beige filled circles indicate the encapsulated Ir complex.