Anna C. Hillier

(PhTe)3−: The Anionic Tellurium Analogue of I3−

The missing link between solid-state tellurium chemistry and polyhalide ions is provided by the synthesis of the almost linear (PhTe)(3)(-) ion, whose structure is shown. Tritelluride units are a recurring motif in the solid state and are related to the structures of polyhalides.

Reactivity of pyrazolylborate complexes of samarium with transition metal carbonyls

Abstract The reaction of [Sm(TpMe,Me)2] with [M(η-C5H4R)(CO)3]2 (M = Cr, R = H; M = Mo, R = Me, tBu; M = W, R = H) gives good yields of [Sm(TpMe,Me)2(μ-OC) M(η-C5H4R)(CO)2]. The crystal structure of the complex for which M = Mo and R = Me has been determined (triclinic, P1¯, a = 10.4106(6), b = 14.1022(8), c = 18.6974(11)A, α = 71.579(2), β = 88.751(2), γ = 85.095(2)° and V = 2594.8(3)A3) confirms the seven coordinate samarium centre with the expected bridging isocarbonyl. In contrast, the reaction of [Sm(TpMe,Me)2] with [Co2(CO)8] gives the salt [Sm(TpMe,Me)2][Co(CO)4] together with [Co4(CO)12].

(PhTe)3−: das anionische Telluranalogon von I3−

Das „missing link” zwischen der Feststoff-Tellurchemie und den Polyhalogenid-Ionen wird durch die Synthese des nahezu linearen (PhTe)3−-Ions hergestellt, dessen Struktur gezeigt ist. Tritellurid-Einheiten sind ein haufig vorkommendes Motiv in der Feststoff-Tellurchemie und strukturell eng mit den Polyhalogeniden verwandt.

The use of pyrazolylborates as ancillaries for lanthanide complexes

[Sm(Tp(Me,Me))(2)] reacts with dichalcogenides to give a series of isoleptic complexes [Sm(Tp(Me,Me))(2)ER] (E = O, S, Se, Te; R = phenyl) which have been structurally characterized. An unusual distortion of the Tp(Me,Me) for the selenolates is discussed in relation to fluxionality and decomposition mechanisms for these complexes. The fluxional behaviour of [Sm(Tp(Me,Me))(2)(S2CNR2)] and [Sm(Tp(Me,Me))(2)(S-2-pyr)] is also described. [Sm(Tp(Me,Me))(2)] reacts with Mn-2(CO)(10) to give [Sm(Tp(Me,Me))(2)]Mn(CO)(5) and small amounts of {[Sm(Tp(Me,Me))(2)](2)(mu-O2CH)}Mn(CO)(5) - effectively the room temperature conversion of CO to formate. The corresponding reaction with Re-2(CO)(10) yields [Sm(Tp(Me,Me))(2)]Re(CO)(5) and [Sm(Tp(Me,Me))(2)](2)Re-4(CO)(17)

Reduction of rhenium decacarbonyl by samarium(II): synthesis and structure of the spiked triangular anion [HRe4(CO)17]−

Abstract The reaction of [Sm(TpMe,Me2)] with [Re2(CO)10] gives [Sm(TpMe,Me2)]Re(CO)5, which on further heating gives moderate yields of [Sm(TpMe,Me)2]2[Re4(CO)17]. Crystallization from toluene yields [Sm(TpMe,Me)2][HRe4(CO)17], which has been crystallographically characterized. It consists of a 64-electron cluster that adopts a spiked triangular structure with the hydride bridging two metal atoms in the equatorial plane of the cluster. A mechanism for the formation of these tetranuclear clusters is proposed.

The reaction of samarium(II) with manganese carbonyl: unexpected conversion of CO to formate. X-ray crystal structures of [Sm(TpMe2)2]Mn(CO)5 and {[Sm(TpMe2)2]2(μ-HCO2)}Mn(CO)5 (TpMe2=HB(3,5-dimethylpyrazolyl)

Abstract The reaction of [Sm(TpMe2)2] with Mn2CO10 results in the reductive cleavage of the Mn–Mn bond and the formation of the salt [Sm(TpMe2)2]Mn(CO)5 which has been characterized by X-ray diffraction (TpMe2=HB(3,5-dimethylpyrazolyl)3). In addition a second product, [(TpMe2)2Sm(μ-O2CH)Sm(TpMe2)2]Mn(CO)5, was isolated and characterized crystallographically. Two mechanisms for the formation of this complex are proposed.

Isocarbonyl complexes of divalent samarium and ytterbium. The molecular structures of [{Ln(TptBu,Me)(THF)(µ-CO)2Mo(η-C5H4Me)(CO)}2] (Ln = Sm, Yb)

The reaction of [Ln(TptBu,Me)I(THF)] (1a Lnxa0=xa0Sm, 1b Lnxa0=xa0Yb) with Na[Mo(η-C5H4Me)(CO)3] gives good yields of [{Ln(TptBu,Me)(THF)(µ-CO)2Mo(η-C5H4Me)(CO)3}2], 2a (Lnxa0=xa0Sm), 2b (Lnxa0=xa0Yb). The low temperature X-ray crystal structures of 2a and 2b have been determined. The structures contain a 12-membered ring of samarium/ytterbium and molybdenum atoms with isocarbonyl groups linking the metal centres. 2a represents the first example of an isocarbonyl bound to samarium(II). Addition of pyridine results in the breakup of the tetramer to give [{Ln(TptBu,Me)(py)n(µ-CO)Mo(η-C5H4Me)(CO)2}2].