To Bond or Not to Bond: Metal-Metal Interaction in Heterobimetallic Rare-Earth Metal-Silver Complexes.

The reaction of 2,4-tBu2-6-(PPh2)PhOH (HOArP) with silver(I) triflate in a 3:1 molar ratio gave the mononuclear coinage metal complex (HOArP-κP)3AgIOTf (1). Treatment of HOArP with LnIII[N(SiMe3)2]3 (Ln = La, Sm, Y, Yb) in a 3:1 molar ratio yielded the mononuclear rare-earth metal complexes LnIII(OArP-κ2O,P)3 (2-Ln). The heterobimetallic rare-earth metal-silver complexes LnIII(OTf)(µ-OArP-1κ1O,2κ1P)3AgI (3-Ln) were prepared from monometallic precursors by reactions of equimolar amounts of 1 with LnIII[N(SiMe3)2]3 or 2-Ln with silver(I) triflate, respectively. The compounds were characterized by NMR, ultraviolet-visible (UV-vis), and infrared (IR) spectroscopy, single-crystal X-ray diffraction, elemental analysis, and the effective magnetic moments of the paramagnetic complexes were determined via the Evans NMR method. Computational studies were conducted on 3-La and 3-Y.

Mono- and Disamarium Azacryptand Complexes: A Platform for Cooperative Rare-Earth Metal Chemistry.

Mono- (H3LSm) and disamarium complexes (LSm2) were prepared by reaction of the azacryptand N[(CH2)2NHCH2-p-C6H4CH2NH(CH2)2]3N (H6L) with 1 or 2 equiv of Sm[N(SiMe3)2]3, respectively. The disamarium complex features free coordination sites on both metal centers available for bridging ligands shielded by phenylenes from tetrahydrofuran (THF) coordination. The reaction of LSm2 with KCN and 18-crown-6 yielded the adduct [LSm2-µ-η1:η1-CN][K(18-crown-6)(THF)2] featuring a bridging cyanide. The complexes were characterized by crystallography, electrochemical analysis, NMR, and optical spectroscopy, and the effective magnetic moments were determined via the Evans method.

Phosphinoindenyl and phosphazidoindenyl complexes of lanthanum and samarium: synthesis, characterisation, and hydroamination catalysis.

The phosphinoindenyl rare-earth metal complexes [1-(Ph2P)-η5-C9H6]2LnIIIN(SiMe3)2, Ln = La (1-La), Sm (1-Sm), were prepared by heating two equivalents of 1-(Ph2P)C9H7 with LnIII[N(SiMe3)2]3 in toluene at 100 °C. The treatment of 1-La with one equivalent of benzonitrile gave (PhCN)[1-(Ph2P)-η5-C9H6]2LaIIIN(SiMe3)2, 2, while no adduct was formed in case of the samarium derivative 1-Sm. The reaction of 1-La and 1-Sm with two equivalents of benzyl azide yielded the (phosphazido)indenyl complexes {1-[BnN3-κN(Ph2)P]-η5-C9H6}{1-[BnN3-κ2N,N'(Ph2)P]C9H6}LnIIIN(SiMe3)2, Ln = La (3-La), Sm (3-Sm), respectively. The five complexes catalyse the intramolecular hydroamination/cyclisation of 2,2-diphenylpent-4-ene-1-amine using 2% catalyst loading. All compounds were characterised by NMR and UV-Vis spectroscopy, single-crystal X-ray diffraction, and elemental analysis and DFT calculations were performed for 3-La.