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Access to highly strained molecules remains a challenge. We report the synthesis of a bench-stable and highly strained (∼135 kcal mol⁻¹) deep cavitand. 

Merging ideas of fullerene tweezers and nanohoops. 

Abstract We report a series of shape‐persistent molecular nanotubes with top rim connectivity traversing from an all‐meta‐ (m₄) to an all‐para‐phenylene (p₄) bridged species, including all possible members in between them. Single‐crystal X‐ray diffraction (SCXRD) and microcrystal electron diffraction (MicroED) data show a large torsional angle formeta‐phenylenes relative topara‐phenylene rings. Density functional theory (DFT) calculations reproduce the experimental torsional angles and also establish a correlation indicating a gradual increase in strain energy fromm₄(∼31 kcal mol⁻¹) top₄(∼90 kcal mol⁻¹). Structural transitions fromm₄top₄lead to additional correlations such as a shift in the lowest absorption wavelength from 330 to 394 nm, a sizeable red shift in the maximum emission wavelength from 444 to 546 nm, and a decrease in fluorescence quantum yield from 0.76 to 0.20, respectively. Time‐dependent (TD)‐DFT analysis of the relaxed excited state (S_1’) geometry shows a progression of exciton delocalization aspara‐phenylenes are introduced intom₄en route top₄, while the overall molecular size remains constant. This effect is directly related to increased π‐conjugation within the nanotube's top‐segment and demonstrates how exciton trapping can take place without changing the nanotube's physical size, e.g., diameter and length. 

Abstract Herein, we report the synthesis of a new series of rigid, allmeta‐phenylene, conjugated deep‐cavity molecules, displaying high binding affinity towards buckyballs. A facile synthetic approach with an overall combined yield of approximately 53% in the last two steps has been developed using a templating strategy that combines the general structure of resorcin[4]arene and [12]cyclo‐meta‐phenylene. These two moieties are covalently linked via four acetal bonds, resulting in a glove‐like architecture.¹H NMR titration experiments reveal fullerene binding affinities (K_a) exceeding ≥10⁶ M⁻¹. The size complementarity between fullerenes and these scaffolds maximizes CH⋯π and π⋯π interactions, and their host:guest adduct resembles a ball in a glove, hence their name as nanogloves. Fullerene recognition is tested by suspending carbon soot in a solution of nanoglove in 1,1,2,2‐tetrachloroethane, where more than a dozen fullerenes are observed, ranging from C₆₀to C₉₆. 

Abstract Template‐assisted synthesis of well‐defined polynuclear clusters remains a challenge for [M₄] square planar topologies. Herein, we present a tetraamine scaffold^RL(NH₂)₄, where L is a rigidified resorcin[4]arene, to direct the formation ofC₄‐symmetric^RL(NH)₄Cu₄clusters with Cu−Cu distances around 2.7 Å, suggesting metal‐metal direct interactions are operative since the sum of copper's van der Waals radii is 2.8 Å. DFT calculations display HOMO to HOMO‐3 residing all within a 0.1 eV gap. These four orbitals display significant electron density contribution from the Cu centers suggesting a delocalized electronic structure. The one‐electron oxidized [Cu₄]⁺species was probed by variable temperature X‐band continuous wave‐electron paramagnetic resonance (CW‐EPR), which displays a multiline spectrum at room temperature. This work presents a novel synthetic strategy for [M₄] clusters and a new platform to investigate activation of small molecules.