Uranium(III)–Phosphorus(III) Synergistic Activation of White Phosphorus and Arsenic

Abstract

The study of small-molecule activation by f-block elements still lags far behind that of transition metals. Although a few uranium complexes have been reported to activate dinitrogen, the reports on the activation of heavier congeners, such as white phosphorus (P 4 ), by uranium species are extremely rare and no example of uranium-mediated activation of elemental arsenic has appeared. Here, we report the first example of uranium-mediated elemental arsenic activation, leading to the formation of a uranium polyarsenide molecular chain with a Z-type As 4 unit. As a comparison, an analogous polyphosphide chain featuring an E-type P 4 unit was generated by the uranium-mediated activation of P 4 . Computational studies show that the U(III)-P(III) synergistic effects allow a direct 6e-reduction of both elemental arsenic and P 4 . The regioselectivity of these reactions is sterically controlled, and the Z-isomer is the thermodynamically favored product whereas the E-isomer is the kinetically favored product. The reactivity of both chains with silylene was also investigated.

Heterometallic Clusters with Uranium–Metal Bonds Supported by Double-Layer Nitrogen–Phosphorus Ligands

“…As a proof of concept, the U(III)−P(III) synergetic strategy was extended to activate P 4 and As 0 (nano) . 51 After treating complex 26 with P 4 at RT for 2 days, complex 30 was isolated and identified as the six-electron reduction of P 4 (Scheme 13). Under similar conditions, an As-activated product, 31, was formed by the reaction of 26 with As 0 (nano) .…”

“…Solid-state molecular structures reveal an E-type activated P 4 unit in 30 and a Z-type As 4 chain in 31 (Figure 15), which are formed by the U(III)−P(III) synergistic activation of P4 and As 0 (nano) . 51 The formation of 31 represents the first example of the uranium-mediated activation of elemental As. The P atoms in the double-layer N−P ligand are important to the formation of complexes 30 and 31.…”

Isolation of uranium(iii) primary phosphido complexes

“…The field of uranium-phosphorus bonds has focused on understanding the electronic structure of these species for applications in small molecule activation, separations, and coordination chemistry. 1 Species featuring these bonds are typically more difficult to make compared to their nitrogen counterparts, preventing wide-spread study. 2 Preliminary work indicates that the stability of these compounds is an issue due to the ''hard-soft'' mismatch of phosphorus with uranium as compared to nitrogen.…”

From a nanoparticular solid-state material to molecular organo-f-element-polyarsenides

“…26 Starting from the nanoscale solid-state material (As 0 nano , d = 7.2 ± 1.8 nm) a variety of new f-element arsenic compounds as well as aluminium arsenic clusters have been successfully synthesised so far. 26–28…”

“…26 Starting from the nanoscale solid-state material (As 0 nano , d ¼ 7.2 AE 1.8 nm) a variety of new f-element arsenic compounds as well as aluminium arsenic clusters have been successfully synthesised so far. [26][27][28] In general, molecular arsenic Zintl ions of the lanthanides were only reported for Sm. In all these reactions the SET pathway from Sm(II) to Sm(III) was applied for the synthesis.…”