Dual molecular tweezers extending from a nanohoop

Abstract

The field of nanohoops is mature enough that synthetic protocols exists to tune their size, composition (incorporation of heteroaromatic building blocks), connectivity (para versus meta linkages), and solubility in different media (hydrophobic versus hydrophilic). Here, we report an additional dimension incorporating the concept of fullerene tweezers into a nanohoop. The resulting hybrid nanohoop is highly strained at 77 kcal mol⁻¹, possesses a quantum yield of 0.12, emits at 584 nm, and displays a positive cooperative binding for C₆₀ (4K₂ ≫ K₁).