Computational insight into asymmetric uranyl-salophen coordinated with cyclohexenone derivatives

The study of the catalytic activity and activation mechanism of asymmetric uranyl‐salophens with α, β‐unsaturated aldehydes or α, β‐unsaturated ketones, is a research hotspot. In this paper, the complexes of the uranyl–salophen(U‐S) modified by unilateral benzene, coordinated with cyclohexenone, cyclopentenone and acrolein, were investigated using density functional theory calculations at the level of B3LYP/6‐311G(d, p) basis set. The results showed that the uranyl‐salophen(U‐S) weakened the large π bond between C = C and C = O of the α, β‐unsaturated aldehydes and ketones, making the unsaturated aldehydes and ketones activated. In addition, the molecular‐recognition selectivity of the asymmetrical uranyl‐salophen for cyclohexenone and cyclopentenone were much higher than for acrolein.

Computational insight into asymmetric uranyl‐salophen coordinated with α, β‐unsaturated aldehydes and ketones

Lan

Meng

et al. 2017

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

Yang

Kong

et al. 2018

Self Cite

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

Long

Peng

et al. 2019

To find new adsorbents for uranyl ions, the density functional theory (DFT) was adopted to design a series of new ligands containing an anthracene and two five-membered heterocycles with nitrogen family nonmetal elements (N, P, As) or oxygen family nonmetal elements (O, S, Se, Te), for example, ligands N,N′-bis(2-five-membered heterocyclidene)-1,8-anthradiamines (BFHADAs).Then the uranyl ions were coordinated with BFHADAs to generate five new coordination complexes (Uranyl-BFHADAs) with heteroatoms N, S, As, Se and Te, respectively. The five-membered heterocyclic rings of Uranyl-BFHADA with oxygen atoms were broken under the structural optimization and Uranyl-BFHADA with heterocyclic atoms P was not obtained. Several structures and property parameters of the ligands BFHADAs (containing heteroatoms N, S, As, Se and Te) and their uranyl complexes Uranyl-BFHADAs were theoretically investigated and analyzed. The results showed that uranyl ions could form stable coordination complexes with these five BFHADAs.The formed bonds between uranyl ions and the heteroatoms in BFHADAs were coordination bonds rather than other types of bonds. These results could provide insightful information and theoretical guidance for the coordination of uranyl with the atoms N, S, Se, As and Te in other ligands.