Synthesis of clusters Fe2(CO)6(μ-XCH2CH=CH2)(μ3-X)Fe(CO)2Cp (X = Se, S; Cp = η5-C5H5)

The clusters Fe₂(CO)₆(μ-XCH₂CH=CH₂)(μ₃-X)Fe(CO)₂Cp (X = S, Se) were prepared by the successive treatment of the bi- and trimetallic complexes Fe₂(CO)₆(μ-Se₂) and Fe₃(CO)₉(μ₃-X) with allylmagnesium chloride and CpFe(CO)₂I. The clusters obtained contain a noncoordinated C=C bond. The structure of the Se-containing cluster was suggested on the basis of comparison of its spectral data (IR,¹H NMR, and Mössbauer spectra) with the spectra of the analogous S-containing complex, which was previously characterized by X-ray diffraction analysis.     

Molecular Polyarsenides of the Rare‐Earth Elements

Reduction of [Cp*Fe(η⁵‐As₅)] with [Cp′′₂Sm(thf)] (Cp′′=η⁵‐1,3‐(tBu)₂C₅H₃) under various conditions led to [(Cp′′₂Sm)(μ,η⁴:η⁴‐As₄)(Cp*Fe)] and [(Cp′′₂Sm)₂As₇(Cp*Fe)]. Both compounds are the first polyarsenides of the rare‐earth metals. [(Cp′′₂Sm)(μ,η⁴:η⁴‐As₄)(Cp*Fe)] is also the first d/f‐triple decker sandwich complex with a purely inorganic planar middle deck. The central As₄^2? unit is isolobal with the 6π‐aromatic cyclobutadiene dianion (CH)₄^2?. [(Cp′′₂Sm)₂As₇(Cp*Fe)] contains an As₇^3? cage, which has a norbornadiene‐like structure with two short As?As bonds in the scaffold. DFT calculations confirm all the structural observations. The As?As bond order inside the cyclo As₄ ligand in [(Cp′′₂Sm)(μ,η⁴:η⁴‐As₄)(Cp*Fe)] was estimated to be in between an As?As single bond and a formally aromatic As₄^2? system.     

Synthesis and structures of new heterometallic clusters [Fe2(MCp x )(CO)6(μ3-S)2] (M = Rh, Ir; Cp x = Cp*, C5H3But 2)

The reaction of the [Fe₂(CO)₆(μ-S)₂]^2? anion (prepared in situ by reduction of [Fe₂(CO)₆(μ-S₂)] with Na/K alloy) with [Cp″RhCl₂]₂ (Cp″ = η⁵-(1,3-Bu^t ₂)C₅H₃) and [Cp*Ir(CH₃CN)₃](CF₃SO₃)₂ (Cp^* is pentamethylcyclopentadienide) yielded new heterometallic clusters [Fe₂(MCp ^x )(CO)₆(μ₃-S)₂]. The core of the resulting clusters can be described as the distorted [Fe₂S₂M] square pyramid with the M atom in the apical position. The structures of the clusters were established by X-ray diffraction.     

Paramagnetic triangular rhenium sulfide cluster [Re3S4(Dppe)3(NCS)3]Br

A new cluster [Re₃S₄(Dppe)₃(NCS)₃]Br (Dppe = Ph₂PCH₂CH₂PPh₂) is synthesized. The molecular and crystal structures of the cluster are determined by X-ray diffraction analysis. The magnetochemical data indicate the high-spin ground state (S = 3/2) of the cluster at room temperature.     

Study of the Possibility of Using Salt Metathesis Reactions for the Synthesis of the Neodymium and Samarium β-Diketiminate Chalcogenide Complexes. Unexpected Reduction of Sm(III) to Sm(II)

Russian Journal of Coordination Chemistry - The possibilities of the ion exchange reactions between the neodymium(III) and samarium(III) diiodo-β-diketiminate complexes...     

Samarium,Europium, and Gadolinium Complexes with 4-(2,1,3-Benzothiadiazol-4-ylamino)pent-3-en-2-onate

Russian Journal of Coordination Chemistry - New lanthanide complexes with 4-(2,1,3-benzothiadiazol-4-ylamino)pent-3-en-2-onate (L–) [Ln(L)3] are synthesized using two methods: by the reaction...     

Synthesis of Unprecedented 4d/4f-Polypnictogens

A series of 4d/4f-polyarsenides, -polyarsines and -polystibines was obtained by reduction of the Mo-pnictide precursor complexes [{Cp^tMo(CO)₂}₂(μ,η^2:2-E₂)] (E=As, Sb; Cp^t=tBu substituted cyclopentadienyl) with two different divalent samarocenes [Cp*₂Sm] and [(Cp^Me4nPr)₂Sm]. For the reductive conversion of the Mo-stibide only one product was isolated, featuring a planar tetrastibacyclobutadiene moiety as an unprecedented ligand for organometallic compounds. For the corresponding Mo-arsenide a tetraarsacyclobutadiene and a second species with a side-on coordinated As₂²⁻ anion was isolated. The latter can be considered as reaction intermediate for the formation of the tetraarsacyclobutadiene.     

The approach to 4d/4f-polyphosphides

The first 4d/4f polyphosphides were obtained by reaction of the divalent metallocenes [Cp*₂Ln(thf)₂] (Ln = Sm, Yb) with [{CpMo(CO)₂}₂(μ,η^2:2-P₂)] or [Cp*Mo(CO)₂(η³-P₃)]. Treatment of [Cp*₂Ln(thf)₂] (Ln = Sm, Yb) with [{CpMo(CO)₂}₂(μ,η^2:2-P₂)] gave the 16-membered bicyclic compounds [(Cp₂*Ln)₂P₂(CpMo(CO)₂)₄] (Ln = Sm, Yb) as the major products. From the reaction involving samarocene, the cyclic P₄ complex [(Cp*₂Sm)₂P₄(CpMo(CO)₂)₂] and the cyclic P₅ complex [(Cp*₂Sm)₃P₅(CpMo(CO)₂)₃] were also obtained as minor products. In each reaction, the P₂ unit is reduced and a rearrangement occurred. In dedicated cases, a P–P bond formation takes place, which results in a new aggregation of the central phosphorus scaffold. In the reactions of [Cp*₂Ln(thf)₂] (Ln = Sm, Yb) with [Cp*Mo(CO)₂P₃] a new P–P bond is formed by reductive dimerization and the 4d/4f hexaphosphides [(Cp*₂Ln)₂P₆(Cp*Mo(CO)₂)₂] (Ln = Sm, Yb) were obtained.     

Unexpected Product of the Reaction of Iron(II) Dichloroclathrochelate with the [Fe2(μ-S)2(CO)6]2– Cluster Dianion: Synthesis and X-ray Diffraction Structure of the First Cage Complex with Thiol Groups Inherently Bonded to a Macrobicyclic Framework

Russian Journal of Coordination Chemistry - An attempt to prepare a hybrid clusteroclathrochelate by nucleophilic substitution of iron(II) dichloroclathrochelate by substitution of its chlorine...