Two Tetra-Nuclear Ln-Substituted Prazine Dicarboxylic Acid-Functionalized Selenotungstates with Catalytic Oxidation of Thioether Properties.

Two two-dimensional Ln-substituted prazine dicarboxylic acid-functionalized selenotungstates Na 3 H 9 [(H 2 N(CH 3 ) 2 ] 2 {(Se 4 W 27 O 100 )[Ln 4 (H 2 O) 8 (Hpzdc) 2 (pzdc)]}·26H 2 O [Ln = Nd ( 1 ) and Ce ( 2 )]; H 2 pzdc = 2,3-pyrazine dicarboxylic acid) have been synthesized by one-pot self-assembly strategy, in which the basic polyanion [Se 4 W 27 O 100 ] 22- was composed of two [SeW 8 O 31 ] 10- fragments, a [SeW 9 O 33 ] 8- segment and an intriguing {SeO} group, simultaneously tetra-nuclear Ln 3+ ions with H 2 pzdc pendants were embedded. Compounds 1 and 2 showed excellent catalytic oxidation of thioether properties within a short time (20 min) with high 100% conversion and 98.9% selectivity. In addition, the pioneering Ln-substituted selenotungstates were used as catalysts to degrade sulfur mustard simulant 2-chloroethyl ethyl sulfide at room temperature with 99% conversion and 100% selectivity. The chemical kinetic experiment studies revealed that the catalytic reaction was in compliance with the first-order reaction, and the kinetic half-life ( t 1/2 ) values were 3.814 and 3.849 min, respectively.