Theoretical investigation into the coordination of R‐/S‐asymmetric uranyl–salophens containing six‐membered ring lactam with cis−/trans‐cyclohexylamines

Abstract

A six‐membered ring lactam derivative was introduced in a parallel manner into uranyl–salophens with R/S configuration (R‐/S‐AUSRLs), which were used as receptors to coordinate with guests of cis−/trans‐methylcyclohexylamines (cis−/trans‐MCHAs). Using density functional theory calculations at the B3LYP/6‐311G** level and RECP, an insight into the coordination complexes of the R‐/S‐AUSRLs with cis−/trans‐MCHAs was obtained. The results showed that the U atoms of receptors could coordinate with the N atoms of four kinds of cis−/trans‐1,2 or − 1,4 guests, but the two kinds of cis−/trans‐1,3 guests could not be converged by the same method in the process of structural optimization due to steric hindrance, and thus the cis−/trans‐1,3 guests could not be coordinated with the R‐/S‐AUSRLs. The mode of coordination of the R‐/S‐AUSRLs with the guests displayed a significant difference. And the change of R‐AUSRL coordination ability to the cis−/trans‐MCHAs was very large, but that of S‐AUSRL was small. Overall, the stability of the R‐series coordination complexes was higher than that of the corresponding S‐series coordination complexes, and the R‐AUSRL receptor had better coordination selectivity and higher molecular recognition to the cis−/trans‐MCHA guests than the S‐AUSRL receptor. However, the coordination ability of S‐AUSRL with the cis−/trans‐MCHAs was stronger than that of R‐AUSRL. It was expected that these results could provide insightful information and theoretical guidance for understanding the molecular recognition of R‐/S‐AUSRLs for cis−/trans‐type cyclohexylamine derivatives.

Insight into Coordination of Uranyl Ions with N,N′‐bis(2‐five‐membered heterocyclidene)‐1,8‐anthradiamines

“…The frontier molecular orbital parameters of the five Uranyl‐BFHADAs with the heteroatoms N, S, As, Se and Te were calculated, respectively, among which E HOMO , E LUMO , Mulliken atomic charges and polarizability ( α ) were directly calculated, and the energy gap ( ΔE L‐H ), chemical hardness ( η ), chemical potential ( Φ ), electronegativity ( χ ) and electrophilicity index ( ω ) of each Uranyl‐BFHADAs were obtained by the following formulas . The calculated results were listed in Table .…”

“…The single point energies and molecular dipole moments of the Uranyl‐BFHADAs under different solvent conditions were calculated using the M062X method and B3LYP method of the density functional theory (DFT), respectively. In the calculation, the quasi relativistic pseudopotential (RECP) basis set was used for the elements after the fourth period such as tellurium and uranium, and the 6‐311G** basis set was used for the elements before the fourth period such as C, H, O, N, P, S, As and Se . In addition, we used Multiwfn to calculate the electron localization function (ELF) curves and the localized orbital locator (LOL) figures, electron density map (EDM) and electron density difference map (EDDM) of the Uranyl‐BFHADAs with the atoms N, S, As, Se and Te, respectively.…”