Non-centrosymmetric superconductor Th[Formula: see text]Be[Formula: see text]Pt[Formula: see text] and heavy-fermion U[Formula: see text]Be[Formula: see text]Pt[Formula: see text] cage compounds.

Unconventional superconductivity in non-centrosymmetric superconductors has attracted a considerable amount of attention. While several lanthanide-based materials have been reported previously, the number of actinide-based systems remains small. In this work, we present the discovery of a novel cubic complex non-centrosymmetric superconductor [Formula: see text] ([Formula: see text] space group).

Acyclic 1,2-dimagnesioethanes/-ethene derived from magnesium(i) compounds: multipurpose reagents for organometallic synthesis.

Reactions of three magnesium(i) dimers, [{(Nacnac)Mg-}] (Nacnac = [(ArNCMe)CH]; Ar = xylyl (Xyl), mesityl (Mes) or 2,6-diethylphenyl (Dep)), with either 1,1-diphenylethylene (DPE), α-methylstyrene (MS), -stilbene (TS) or diphenylacetylene (DPA) led to the 1,2-addition of the Mg-Mg bond across the substrate, giving rise to the 1,2-dimagnesioethanes, [{(Nacnac)Mg}(μ-DPE)], [{(Nacnac)Mg}(μ-MS)], [{(Nacnac)Mg}(μ-TS)] (Ar = Mes or Dep); and a 1,2-dimagnesioethene, [{(Nacnac)Mg}(μ-DPA)]. The reactions involving the 1,1-substituted alkenes are shown to be readily redox reversible, in that the reaction products are in equilibrium with a significant proportion of the starting materials at room temperature. Variable temperature NMR spectroscopy and a van't Hoff analysis point to low kinetic barriers to these weakly exergonic reactions.

Synthesis and Reactivity Studies of Amido-Substituted Germanium(I)/Tin(I) Dimers and Clusters.

Three amide ligands of varying steric bulk and electronic properties were utilized to prepare a series of amido-germanium(II)/tin(II) halide compounds, (LEX) , (L= -N{B(DipNCH) }(SiMe ), L; -N{B(DipNCH) }(SiPh ), L; -N(Dip)(tBu), L; Dip=C H iPr -2,6; E=Ge or Sn; X=Cl or Br; n=1 or 2). Reductions of these with a magnesium(I) dimer, {( Nacnac)Mg} ( Nacnac=[(MesNCMe) CH] , Mes=mesityl), afforded singly bonded amido-digermynes ( LGe-Ge L and LGe-Ge L), and an amido-distannyne ( LSn-Sn L), in addition to several low-valent, amido stabilized tetrel-tetrel bonded cluster compounds, ( LGe) , ( LSn) and Sn ( L) . The nature of the products resulting from these reactions was largely dependent on the steric bulk of the amide ligand employed.

An acyclic zincagermylene: rapid activation of dihydrogen at sub-ambient temperature.

The first example of a stable zincagermylene, :Ge(TBoN)(ZnL*) (TBoN = N(SiMe){B(DipNCH)}, Dip = CHPr-2,6; L* = -N{CH[C(H)Ph]Me-2,6,4}(SiPr)) is prepared and shown to have unprecedented reactivity for a germylene, with respect to the activation of dihydrogen. Computational analyses point towards this being partially derived from the electron releasing nature of the amido-zinc fragment, which leads to a narrowing of the HOMO-LUMO gap in the compound.

Two-coordinate terminal zinc hydride complexes: synthesis, structure and preliminary reactivity studies.

The first examples of essentially two-coordinate, monomeric zinc hydride complexes, LZnH (L = -N(Ar)(SiR3)) (Ar = C6H2{C(H)Ph2}2R'-2,6,4; R = Me, R' = Pr(i) (L'); R = Pr(i), R' = Me (L*); R = Pr(i), R' = Pr(i) (L(†))) have been prepared and shown by crystallographic studies to have near linear N-Zn-H fragments. The results of computational studies imply that any PhZn interactions in the compounds are weak at best. Preliminary reactivity studies reveal the compounds to be effective for the stoichiometric hydrozincation and catalytic hydrosilylation of carbonyl compounds.