Multi-electron reduction of sulfur and carbon disulfide using binuclear uranium(iii) borohydride complexes

Abstract

The first use of a dinuclear UIII/UIII complex in the activation of small molecules is reported.

Selective oxo ligand functionalisation and substitution reactivity in an oxo/catecholate-bridged UIV/UIV Pacman complex

“…In the solid-sate structure ( Fig. 3A ), the U–S bond lengths range from 2.782(1)–2.791(1) Å and are similar to those in [{U IV (OAr)} 2 (μ-η 2 :η 2 -S 2 )(L A )] (OAr = OC 6 H 2 -2,4,6- t Bu 3 ), which range from 2.707(3)–2.8229(8) Å, 29 but are significantly shorter than those in [{U IV (Tren TIPS )} 2 (μ-η 2 :η 2 -S 2 )] (Tren TIPS = N(CH 2 CH 2 NSi i Pr 3 ) 3 ) and [{U IV {(SiMe 2 NPh) 3 -tacn}} 2 (μ-η 2 :η 2 -S 2 )] ((Me 2 SiNHPh) 3 -tacn = 1,4,7-tris((dimethylsilyl)phenylamino)-1,4,7-triazacyclononane) which range from 2.867(1)–2.928(2) Å ( ref. 30 ) and 2.855(2)–2.907(3) Å, 31 respectively.…”

Pacman Compounds: From Energy Transfer to Cooperative Catalysis

“…Thirdly, also in 2017, Love and co‐workers demonstrated the multi‐electron reduction of sulfur and carbon disulfide using diuranium complexes . The complex is based on the Schiff‐base anthracene‐hinged ligand already presented in Figure (left).…”

Oligonuclear Actinoid Complexes with Schiff Bases as Ligands—Older Achievements and Recent Progress

“…The Pacman macrocycles (H4 R L 1 , Figure 13; H4 R L A , Figure 18) have also been used for the synthesis of dinuclear U(IV) complexes. Complexes [U IV 2(OAr)2(S2)( Et L A )] (72) and [U IV 2(OAr)2(S)( Et L A )] (73) have been obtained by reactivity studies of the soluble complex [KU III 2 (OAr)2(BH4)( Et L A )(THF)2] (81), vide infra; the alkoxide OAr − is OC6H2 t Bu3-2,4,6 [121]. Addition of an excess of S8 to a slurry of 81 in toluene resulted in the isolation of the thermally stable product 72 in 41% yield; Equation (24).…”

“…The BH 4 − /( Et L A ) 4− "blend" has also been used to stabilize the dinuclear complexes Table 4) by aryloxido ligands [121]. The reactions result in a single, weakly bound, encapsulated endo Na I or K I borohydride bridging the two U III centers.…”

“…The BH4 − /( Et L A ) 4− "blend" has also been used to stabilize the dinuclear complexes [MU III 2(OAr)2(BH4)( Et L A )(THF)2] (M = Na, 80; M = K, 81), where Oar = OC6H2 t Bu3-2,4,6. These complexes can be prepared by substitution of the terminal BH4 − ligands [those bound to U III outside the macrocyclic cleft of ( Et L A ) 4− ] of 79 and its K I -analogue (not shown in Table 4) by aryloxido ligands [121]. The reactions result in a single, weakly bound, encapsulated endo Na I or K I borohydride bridging the two U III centers.…”