Understanding the interplay between π–π and cation–π interactions in [janusene–Ag]⁺ host–guest systems: a computational approach

Abstract

Guiding the development of new systems with increased cation–π interaction capability.

Rivalry between Regium and Hydrogen Bonds Established within Diatomic Coinage Molecules and Lewis Acids/Bases

“…The interplay between π-π and π-Ag interactions were analysed using the janusene framework. [23] The AgÀ Ag distance in regium bonded complexes between dinuclear silver pyrazolate molecules and Lewis bases have shown to depend on the number of ligands interacting with the silver atoms and the nature of the substituents on the pyrazole units. [24] The NMR shifts of ninemembered rings formed by trinuclear silver pyrazolate com-plexes were measured and computed using ZORA relativistic method.…”

“…Silver derivatives have also been subject to study. The interplay between π‐π and π‐Ag interactions were analysed using the janusene framework [23] . The Ag−Ag distance in regium bonded complexes between dinuclear silver pyrazolate molecules and Lewis bases have shown to depend on the number of ligands interacting with the silver atoms and the nature of the substituents on the pyrazole units [24] .…”

Janusene as a silver ion scavenger: insights from computation

“…20,21 Based on the evidence of the presence of p-p transannular interactions in the janusene framework, a recent study has been published by our group, which assessed the interplay between cation-p and p-p interactions by allowing a silver cation (Ag + ) to interact with the different aromatic portions of janusene, in conjunction with the presence of both EDG electron donating and EWG electron withdrawing groups. 18 Among the eight possible coordination sites, previously observed, 18 six have converged to a minimum of energy, according to Fig. 2, where the B position provides the most stable cation-p situation.…”

“…1). It is considered that a [3,3]ortho-cyclophane possesses four aromatic moieties of which two moieties, due to it's strained geometry, are held together in a quasi-parallel or a cleft-shaped arrangement, in which the typical C-C distances vary from 2.987 Å in C ipso to 4.094 Å in C b 17,18 (Fig. 1).…”

“…Such proximity between these aromatic portions enables janusene to exhibit peculiar electronic properties, which have been evidenced from both experimental and theoretical perspectives. 15,[17][18][19][20][21][22] Experiments have shown that the reactivity of the janusene is critically influenced by the proximity of the facial rings. Regarding electrophilic aromatic substitutions, they occur preferentially on the beta carbons of the facial rings, F b , 15,19 due to transannular interactions that destabilize the ground state (GS) through p-repulsion and stabilize the transition state (TS) through p-delocalization.…”