The [Cl2OMo(μ-OC2H5)2(μ-HOC2H5)MoOCl2]/PMe3 System: A Chameleon Yielding the X-ray Structures of MoOCl2(PMe3)3, MoOCl3(PMe3)2, Mo4O4Cl4(μ2-OEt)4(PMe3)2(μ3-O)2, and MoOCl3(OPMe3)(PMe3)

Synthesis, properties and structural features of molybdenum(v) oxide trichloride complexes with neutral chalcogenoether ligands

Complexes of oxotrichloromolybdenum(v) with neutral group 16 donor ligands, [MoOCl₃(L-L)] (L-L = RS(CH₂)₂SR, R = ⁱPr, Ph; MeS(CH₂)₃SMe; MeSe(CH₂)₂SeMe; MeSe(CH₂)₃SeMe), [{MoOCl₂(EMe₂)}₂(μ-Cl)₂] (E = S, Se, Te), [(MoOCl₃)₂{o-C₆H₄(EMe)₂}]_n (E = Se or Te) and [(MoOCl₃)₂{MeTe(CH₂)₃TeMe}]_n, have been obtained by reaction of the ligands with [MoOCl₃(thf)₂] or MoOCl₃ in either CH₂Cl₂ or toluene, and characterised by microanalysis, IR and UV-visible spectroscopy and magnetic measurements. The telluroethers are the first examples containing Mo in a positive oxidation state. X-ray crystal structures are reported for the six-coordinate fac-[MoOCl₃{MeS(CH₂)₃SMe}], mer-[MoOCl₃{ⁱPrS(CH₂)₂SⁱPr}] and mer-[MoOCl₃{MeSe(CH₂)₂SeMe}], as well as the six-coordinate chloride-bridged dimers, [{MoOCl₂(SMe₂)}₂(μ-Cl)₂] and [{MoOCl₂(SeMe₂)}₂(μ-Cl)₂]. The structure of the mixed-valence decomposition product, [Mo^IVCl{o-C₆H₄(TeMe)₂}₂(μ-O)Mo^VOCl₄], was also determined. In toluene solution MoOCl₄ is reduced by MeS(CH₂)₃SMe to produce the Mo(v) complex, [MoOCl₃{ MeS(CH₂)₃SMe}]. Crystal structures of the previously unknown diphosphine analogue, [MoOCl₃{Me₂P(CH₂)₂PMe₂}], and the mixed-valence derivative [Mo^IVCl{Me₂P(CH₂)₂PMe₂}₂(μ-O)Mo^VOCl₄] are also reported for comparison and help to clarify earlier contradictory literature reports. In contrast to the dimeric EMe₂ complexes, [{MoOCl₂(EMe₂)}₂(μ-Cl)₂], PMe₃ forms the monomeric complex, fac-[MoOCl₃(PMe₃)₂].

Crystal structure and Hirshfeld surface analysis of the elusive trichlorobis(diethyl ether)oxomolybdenum(V)

First reported in 1930, MoCl3O(Et2O)2 is a by-product of the reductive synthesis of MoCl4(OEt2)2 from MoCl5. We report herein the X-ray crystal structure and Hirshfeld surface characteristics of mer-MoCl3O(Et2O)2, or [MoCl3O(C4H10O)2]. The compound crystallizes in the orthorhombic space group P212121. The molybdenyl (Mo=O) bond length is 1.694 (3) Å and the cis- and trans-Mo—O distances are 2.157 (3) and 2.304 (3) Å, respectively. Intermolecular Mo=O...H bonding is present in the lattice, with the shortest distance being 2.572 Å.

Ni(3)(Mo(2)O(8))(XO(3)) (X = Se, Te): the first nickel selenite- and tellurite-containing Mo4 clusters

Two new nickel(II) molybdenum(VI) selenium(IV) and tellurium(IV) oxides generally formulated as Ni3(Mo2O8)(XO3) (X = Se, Te) have been synthesized by solid-state reactions of NiO, MoO3, and SeO2 (or TeO2). Both compounds feature 3D network structures built of [Mo4O16]8- tetranuclear cluster units and 2D nickel(II) selenite or tellurite layers. The nickel(II) selenite layer in Ni3(Mo2O8)(SeO3) is formed by [Ni6O22]32- hexanuclear clusters interconnected by selenite groups whereas the thick nickel(II) tellurite layer in Ni3(Mo2O8)(TeO3) is constructed by corrugated nickel(II) oxide chains bridged by the tellurite groups. The results of magnetic property measurements indicate that there are considerable ferromagnetic interactions between nickel(II) centers in both compounds. Their optical properties and band structures have been also studied.