Pyridinium encapsulation within a novel cyano-footed pyrogallol[4]arene nanocapsule

Abstract

A novel polar solvent-soluble tetra-functionalised cyano-footed calixarene forms a dimeric capsule, sealed via a hydrogen-bonding network between the two macrocycles, a single water molecule and a chloride anion, resulting in the encapsulation of a pyridinium guest, as shown in both solution and the solid state.

Keywords::

• pyrogallol[4]arene
• macrocycle
• nanocapsule
• host–guest
• calixarene

Acknowledgements

The authors thank Mr N. Fujii (Jeol UK) for assistance with diffusion NMR experiments, Nottingham Trent University and National Eye Research Centre for funding.

Notes

^1. Crystallographic data: C₁₄₉H₂₀₈ClN₉O₂₅, M_r = 2560.74, colourless block, 0.40 × 0.35 × 0.30 mm³, monoclinic, space group C2/c (No. 15), a = 34.0663(17), b = 12.5680(6), c = 34.7846(16) Å, β = 107.054(2)°, V = 14238.0(12) Å³, Z = 4, D_c = 1.192 g/cm³, Bruker X8 Apex II CCD Diffractometer, MoK_α radiation, λ = 0.71073 Å, T = 100(2) K, 2θ_max = 46.6°, 37,394 reflections collected, 10,185 unique (R_int = 0.0451). Final GooF = 1.915, R₁ = 0.0982, wR₂ = 0.2704, R indices based on 6408 reflections with I>2σ(I) (refinement on F²). CCDC reference number 701056 for crystallographic data in CIF or other electronic format.