Monomeric Rare‐Earth Metal Silyl‐Thiophosphinoyl‐Alkylidene Complexes: Synthesis, Structure, and Reactivity. Issue 52 (22nd August 2018)

• Record Type: Journal Article
• Authors: Wang, Chen; Mao, Weiqing; Xiang, Li; Yang, Yan; Fang, Jian; Maron, Laurent; Leng, Xuebing; Chen, Yaofeng
• Is Part Of: Chemistry. Volume 24:Issue 52(2018)
• Page Start: 13903
• Page End: 13917
• Publication Date: 2018-08-22
• Subjects: density functional calculations -- insertion -- multiple bonds -- rare earths -- X-ray diffraction; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201802791
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: A series of monomeric rare‐earth metal silyl‐thiophosphinoyl‐alkylidene complexes [LLn{C(SiR3 )PPh2 S}] (5 : Ln=Lu, R=Me;6 : Ln=Lu, R=Ph;7 : Ln=Y, R=Me;8 : Ln=Y, R=Ph;9 : Ln=Sm, R=Ph;10 : Ln=Sm, R=Me;11 : Ln=La, R=Ph; L=[MeC(NDIPP)CHC(Me)(NCH2 CH2 N(Me)2 )] −, DIPP=2, 6‐( i Pr)2 C6 H3 ) have been synthesized and structurally characterized. The influences of rare‐earth metal ions, ancillary ligands, and alkylidene groups on the reactivity of complexes5 –11 and the related scandium complexes [LSc{C(SiR3 )PPh2 S}] (1 : R=Me;2 : R=Ph) and [L′Sc{C(SiR3 )PPh2 S}] (3 : R=Me;4 : R=Ph; L′=[MeC(NDIPP)CHC(Me)(NCH2 CH2 N( i Pr)2 )] − ) have been studied. Reactions of these rare‐earth metal alkylidene complexes with PhCN give four kinds of products, the formation of which is dependent on the rare‐earth metal ions, ancillary ligands, and alkylidene groups of the complexes. In the reactions with t BuNC, unusual C−P bond cleavage of the alkylidene group and C≡C triple bond formation occur. Complexes10 and11 also react with PhSiH3 to form hydrides, which subsequently undergo Ln−H addition to the C=N bond of the ancillary ligand L. DFT calculations have been used to analyze the bonding in complex10, which exhibits a polarized three centers Sm−C−P π interaction, and to rationalize the reactivity by computing reaction mechanisms. The difference in reactivity of PhCN and t BuNC is due to the electron density delocalization that is enabled by the phenyl group rather than the t Bu group. Abstract : Rare‐earth complexes : Monomeric silyl‐thiophosphinoyl‐alkylidene complexes [LLn{C(SiR3 )PPh2 S}] of four different trivalent rare‐earth metals, which even include the rare‐earth meal ion with the largest ionic radius (La 3+ ), are synthesized and structurally characterized (see picture). The influences of rare‐earth metal ions, ancillary ligands, and alkylidene groups on the reactivity of these complexes and the related scandium complexes are studied.