The rational design and synthesis of the Trapen ligand (1, tris­(2-aminobenzyl)­amine) with a tripodal scaffold is reported. Treatment of Trapen with n-BuLi and TMSCl results in the formation of the corresponding complex [(TrapenTMS)­(Li)3] (2). In particular, 2 reacts with UCl4 to give the important synthon uranium­(IV) complex [U­(TrapenTMS)­(Cl)] (3) with all of the nitrogen atoms bound to the uranium­(IV) center. Moreover, the pseudohalogen congener [U­(TrapenTMS)­(OCP)] (4) or the azide analogue [U­(TrapenTMS)­(N3)] (5) could be obtained when [U­(TrapenTMS)­(Cl)] (3) was treated with NaOCP­(dioxane)2.5 or NaN3 by a salt metathesis approach. In addition, the reaction of KC8 with [U­(TrapenTMS)­(Cl)] (3) did not afford the desired U­(III) complex but produced the unexpected bridging diuranium oxo complex [U­(TrapenTMS)2(μ-O)] (6). All of the compounds were isolated in the solid state and characterized by NMR, X-ray crystal diffraction, and FT-IR, and UV–vis–NIR as well as elemental analyses and SQUID magnetization measurements. The combined experimental analyses and chemical calculations support all of the formal uranium­(IV) species.

In order to explore the enantioselectivity of new uranyl receptors to chiral organophosphorus pesticides (COPs), we designed a novel ligand: 2‐(2‐hydroxy‐3‐methoxyphenyl)‐9‐(2‐hydroxyphenyl)thiopyrano[3,2‐h]thiochromene‐4,7‐dione (HTTDN) and constructed a new receptor of Uranyl‐HTTDN by complexation of HTTDN with uranyl. The complexation and enantioselectivity of Uranyl‐HTTDN to COPs of R/S‐methamidophos (R/S‐MAPs) and R/S‐acephates (R/S‐APs) were studied using density functional theory (DFT) method in this paper. The results showed that in vacuum and toluene, Uranyl‐HTTDN could effectively recognize R/S‐MAPs by complexation with oxygen of phosphoryl of methamidophos, with enatioselectivity coefficients of 91.80% and 86.74%, respectively. In vacuum, water, and acetone, Uranyl‐HTTDN could also effectively identify R/S‐APs by the oxygen of phosphoryl coordinating with U, and enatioselectivity coefficients toward R/S‐APs were 99.41%, 91.09%, and 93.84%, respectively. These results could provide valuable information and theoretical reference for the further experiments of COPs separation.

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