Metathesis of a UV imido complex: a route to a terminal UV sulfide. Issue 8 (5th June 2017)

• Record Type: Journal Article
• Authors: Kelly, Rory P.; Falcone, Marta; Lamsfus, Carlos Alvarez; Scopelliti, Rosario; Maron, Laurent; Meyer, Karsten; Mazzanti, Marinella
• Is Part Of: Chemical science. Volume 8:Issue 8(2017)
• Page Start: 5319
• Page End: 5328
• Publication Date: 2017-06-05
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7sc01111c
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : The metathesis reaction of a U V imido complex supported by sterically demanding tris( tert -butoxy)siloxide ligands with CS2 afforded a terminal U V thiocarbonate but metathesis with H2 S afforded the first example of a terminal U V sulfide. Abstract : Herein, we report the synthesis and characterisation of the first terminal uranium(v ) sulfide and a related U V trithiocarbonate complex supported by sterically demanding tris( tert -butoxy)siloxide ligands. The reaction of the potassium-bound U V imido complex, [U(NAd){OSi(O t Bu)3 }4 K] (4 ), with CS2 led to the isolation of perthiodicarbonate [K(18c6)]2 [C2 S6 ] (6 ), with concomitant formation of the U IV complex, [U{OSi(O t Bu)3 }4 ], and SCNAd. In contrast, the reaction of the U V imido complex, [K(2.2.2-cryptand)][U(NAd){OSi(O t Bu)3 }4 ] (5 ), with one or two equivalents of CS2 afforded the trithiocarbonate complex, [K(2.2.2-cryptand)][U(CS3 ){OSi(O t Bu)3 }4 ] (7 ), which was isolated in 57% yield, with concomitant elimination of the admantyl thiocyanate product, SCNAd. Complex7 is likely formed by fast nucleophilic addition of a U V terminal sulfide intermediate, resulting from the slow metathesis reaction of the imido complex with CS2, to a second CS2 molecule. The addition of a solution of H2 S in thf (1.3 eq.) to4 afforded the first isolable U V terminal sulfide complex, [K(2.2.2-cryptand)][US{OSi(O t Bu)3 }4 ] (8 ), in 41% yield. Based on DFT calculations, triple-bond character with a strong covalent interaction is suggested for the U–S bond in complex7 .