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A new concept of ligand ambiphilicity that relies on the redox behavior of the indirectly coordinated boron cluster scaffold instead of the direct involvement of a single center in a ligand is introduced. 

Achieving tunable electrical conductivity in organic materials is a key challenge for the development of next-generation semiconductors. This study demonstrates a novel approach using triphenylamine (TPA) bis-urea macrocycles as supramolecular hosts for guest-induced modulation of charge-transfer (CT) properties. By encapsulating guests with varying reduction potentials, including 2,5-dichloro-1,4-benzoquinone (ClBQ), 2,1,3-benzothiadiazole (BTD), and malononitrile (MN), we observed significant changes in the electrical conductivity. Crystals of the 1(ClBQ)0.31 complex exhibited an electrical conductivity of ∼2.08 × 10–5 S cm–1, a 10,000-fold enhancement compared to the pristine host. This is attributed to efficient CT observed in spectroscopic analyses and is consistent with the computed small HOMO–LUMO gap (2.92 eV) in a model of the host–guest system. 1(MN)0.39 and 1(BTD)0.5 demonstrated moderate conductivities explained by the interplay of electronic coupling, reorganization energy, and energy gap. Lower ratios of guest inclusion decreased the electrical conductivity by 10-fold in 1(ClBQ)0.18, while 1(MN)0.25 and 1(BTD)0.41 were nonconductive (10–9 S cm–1). This work highlights the potential of metal-free, porous organic systems as tunable semiconductors, offering a pathway to innovative applications in organic electronics. 

Photochromic radionuclide-based “claw machines” characterizedviaa combination of isothermal titration calorimetry and spectroscopic analysis unlock a pathway for on demand radionuclide capture and release. 

The structures and photoinduced radical (PIR) percentages of two crystalline solvates of unsubstituted triphenylamine bis-urea macrocycles are compared. Upon activation, both afford similar structures with higher PIR %.