Investigating Steric and Electronic Effects in the Synthesis of Square Planar 6d¹ Th(III) Complexes

Inorganic Chemistry, Год журнала: 2024, Номер 63(14), С. 6217 - 6230

Опубликована: Март 19, 2024

The factors affecting the formation and crystal structures of unusual 6d1 Th(III) square planar aryloxide complexes, as exemplified by [Th(OArMe)4]1– (OArMe = OC6H2tBu2-2,6-Me-4), were explored synthetic reduction studies a series related Th(IV) tetrakis(aryloxide) Th(OArR)4 (OArR OC6H2tBu2-2,6-R-4). Specifically, electronic, steric, countercation effects varying ligand, alkali metal reducing agent, chelating agent. Salt metathesis reactions between ThBr4(DME)2 (DME 1,2-dimethoxyethane) 4 equiv appropriate potassium salt used to prepare complexes in high yields: Th(OArH)4 (OArH OC6H3tBu2-2,6), Th(OArtBu)4 (OArtBu OC6H2tBu3-2,4,6), Th(OArOMe)4 (OArOMe OC6H2tBu2-2,6-OMe-4), Th(OArPh)4 (OArPh OC6H2tBu2-2,6-Ph-4). can be reduced KC8, Na, or Li absence presence 2.2.2-cryptand (crypt) 18-crown-6 (crown) form dark purple solutions that have EPR UV–visible spectra similar those complex, [Th(OArMe)4]1–. Hence, para position ligand does not alkylated obtain complexes. Furthermore, Th(OArOMe)4, Th(OArtBu)4, with KC8 THF generated are previously reported anion, Although many these did produce single crystals suitable for study X-ray diffraction, Th(OArH)4, provided quality whose had coordination geometries. Reduction also gave product matched [Th(OArMe)4]1–, but too unstable provide data. Neither Th(Odipp)4(THF)2 (Odipp OC6H3iPr2-2,6) nor Th(Odmp)4(THF)2 (Odmp OC6H3Me2-2,6) could products under conditions. U(OArH)3(THF) was examined comparison formed [K(crypt)][U(OArH)4], which has tetrahedral arrangement ligands. Moreover, no further observed when either [K(crypt)][U(OArH)4] [K(crown)(THF)2][U(OArH)4] treated Li.

Язык: Английский

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Enhancing blocking temperature using inverse hydrogen bonds for non-radical bridged dimeric Dy(III) single-molecule magnets

Science China Chemistry, Год журнала: 2024, Номер 67(10), С. 3328 - 3338

Опубликована: Авг. 19, 2024

Язык: Английский

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A rare case of a zero-field single-ion magnet in a cerium(iii) pseudo-icosahedral complex

Dalton Transactions, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

The synthesis of the isomorphous series [Ln(Tp 2-Fu ) 2 ]I ( 1-Ln , Ln = La, Ce, Pr, Nd) is reported, with a rare case zero-field single-ion magnetic behaviour in 1-Ce producing one highest energies barriers to slow relaxation cerium-based complexes.

Язык: Английский

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Synthesis and structure of trinuclear yttrium(III) dihydrido cluster stabilized by bulky amidinate ligand

Mendeleev Communications, Год журнала: 2025, Номер 35(1), С. 31 - 34

Опубликована: Янв. 1, 2025

Язык: Английский

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Multimetallic Half-Sandwich Complexes of the Rare-Earth Metals

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 31, 2025

Multimetallic half-sandwich complexes of the paramagnetic lanthanides gadolinium, terbium, dysprosium, holmium, and erbium as well diamagnetic yttrium are readily accessible via AlMe4/halogenido exchange reactions Cp*Ln(AlMe4)2 with mild halogenido transfer reagents Me3SiI Me3GeX (Cp* = C5Me5; X Br, Cl). Depending on rare-earth-metal center ion size, distinct structural motifs nuclearities obtained, including dimeric compounds [Cp*Ln(AlMe4)(μ2-Cl)]2 for smaller metal centers Ln Ho, Er, iodido-bridged tetranuclear rings [Cp*Ln(μ2-I)2]4 (Ln Y, Tb, Dy, Er), a heterobimetallic tetramethylaluminato-bridged gadolinium cluster [Cp*4Gd4I7(AlMe4)]2. The dysprosium complex [Cp*Dy(μ2-I)2]4 shows single-molecule magnet (SMM) behavior in zero applied field an effective energy barrier 164(10) cm-1.

Язык: Английский

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Anomalous Magnetic Hysteresis up to 20 K in a Non‐Kramers Light‐Lanthanide Single‐Molecule Magnet

Angewandte Chemie International Edition, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

Abstract Light‐lanthanides (Ln), despite their widespread uses in commercial permanent magnets, are among the least explored metal elements as building blocks of single‐molecule magnets (SMMs) due to smaller magnetic moments well weaker spin–orbit couplings than those heavy‐Ln counterparts, and so far, only a neodymium (Nd) complex has been reported showing small hysteresis at 2 K. Here, we report low‐coordination praseodymium (Pr) complex, namely, Pr@C 81 N, featuring non‐Kramers trivalent Pr ion entrapped within an azafullerene cage behaving first Pr‐based SMM. Although weak nonaxial ligand field imposed by carbon on integer‐spin Pr(III) elicits nondegenerate spin states, N shows anomalous up 20 K using sweep rate Oe/s, which is highest temperature all light‐Ln SMMs. In addition ideally minimized spin–phonon coupling low coordination, origin such unexpected bistability for likely lies nuclear sublevels arising from large hyperfine coupling, feature distinct electronic magnetizations highly mixed ground state.

Язык: Английский

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Anomalous Magnetic Hysteresis up to 20 K in a Non‐Kramers Light‐Lanthanide Single‐Molecule Magnet

Angewandte Chemie, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

Abstract Light‐lanthanides (Ln), despite their widespread uses in commercial permanent magnets, are among the least explored metal elements as building blocks of single‐molecule magnets (SMMs) due to smaller magnetic moments well weaker spin–orbit couplings than those heavy‐Ln counterparts, and so far, only a neodymium (Nd) complex has been reported showing small hysteresis at 2 K. Here, we report low‐coordination praseodymium (Pr) complex, namely, Pr@C 81 N, featuring non‐Kramers trivalent Pr ion entrapped within an azafullerene cage behaving first Pr‐based SMM. Although weak nonaxial ligand field imposed by carbon on integer‐spin Pr(III) elicits nondegenerate spin states, N shows anomalous up 20 K using sweep rate Oe/s, which is highest temperature all light‐Ln SMMs. In addition ideally minimized spin–phonon coupling low coordination, origin such unexpected bistability for likely lies nuclear sublevels arising from large hyperfine coupling, feature distinct electronic magnetizations highly mixed ground state.

Язык: Английский

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New pyridyl-containing amidine and specific features of its coordination to K+ and La3+ ions

Russian Chemical Bulletin, Год журнала: 2025, Номер 74(1), С. 83 - 93

Опубликована: Янв. 1, 2025

Язык: Английский

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Redox Studies of the Scandium Metallocene (C₅H₂^tBu₃)₂Sc^II Lead to a Terminal Side-On (N═N)^2– Complex: [(C₅H₂^tBu₃)₂Sc^III(η²-N₂)]⁻

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Март 31, 2025

Cyclic voltammetry measurements on the scandium(II) metallocene, Cpttt2ScII (Cpttt = C5H2tBu3), reveal a -1.87 V vs Fc+/Fc event assigned to [Cpttt2Sc]+/0 redox couple and -3.09 process [Cpttt2Sc]0/- couple, which are consistent with subsequent chemical studies. Chemical oxidation of AgBPh4 gives scandocenium cation salt [Cpttt2ScIII][BPh4], 1. The [Cpttt2ScIII]+ does not coordinate [BPh4]- anion or THF solvent; however, one methyl groups tert-butyl substituent has close interaction Sc(III) ion. Decomposition occurs in presence [nBu4N][PF6] supporting electrolyte, studies indicate that 1 reacts [PF6]- by fluoride abstraction form Cpttt2ScIIIF PF5. reduction proceeds Cp*2SmII Cp*2CoII (Cp* C5Me5), is measured potentials. was observed react N2; treatment KC8 18-crown-6 (crown) under N2 forms (N═N)2- complex, Cpttt2ScIII(μ-η2:η2-N2)K(crown), 2. reaction 2.2.2-cryptand (crypt) generates [K(crypt)][Cpttt2ScIII(η2-N2)], 3, first isolable complex any metal terminal side-on ligand. These LnIIA2/M/N2 reactions (M alkali metal; (A)- anion) Ln(II)/Ln(I) analogs previously reported Ln(III)/Ln(II) reactions, LnIIIA3/M/N2, Ln(III) complexes Ln(II) reactivity complexes.

Язык: Английский

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Synthesis, X-Ray Crystal Structures, and Magnetic Properties of a Series of Trinuclear Rare-Earth Hepta-Chloride Clusters

Magnetochemistry, Год журнала: 2025, Номер 11(5), С. 38 - 38

Опубликована: Май 2, 2025

Organometallic rare-earth complexes have attracted considerable attention in recent years due to their unique structures and exceptional magnetic properties. In this study, we report the synthesis characteristics of a family monopentamethylcyclopentadienyl-coordinated trinuclear hepta-chloride clusters [(Li(THF)(Et2O))(Cp*RE)3(μ-Cl)4(μ3-Cl)2(μ4-Cl)] (RE3: RE =Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu; Cp* = pentamethylcyclopentadienide). These were synthesized by reacting LiCp* with RECl3 1:1 molar ratio within mixed solvent system (THF: Et2O 1:9), resulting high solubility common organic solvents such as DCM, THF, Et2O. Magnetic studies conducted on these paramagnetic reveal coexistence ferromagnetic antiferromagnetic superexchange interactions Gd3. Additionally, Dy3 exhibits both intramolecular dipolar interactions. Notably, slow relaxation was observed below 23 K under zero DC applied field an energy barrier 125(6) cm−1.

Язык: Английский

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