Novel calix[4]cryptands: “Mappemonde II” and “Mill II”

Two novel calix[4]cryptands were synthesized from 1,3‐alternate calix[4]bis‐azacrown. “Mappemonde II” consists of one 1,3‐calix[4]bis‐azacrown wrapped by a benzo‐crown ether loop. “Mill II” is composed of two 1,3‐calix[4]bis‐azacrowns linked by two benzo‐crown ether strands.     

The Mixed Valence Structure of “R–NiF3”

XAS at the nickel K-edge and UV-visible studies of rhombohedral nickel trifluoride indicate that the compound has a mixed valence composition Ni[NiF₆] and is isostructural with Pd[PdF₆]. XAS data are reported for NiF₂, [NiF₆]^2–, [NiF₆]^3–, Pd[PdF₆], CoF₃ and RhF₃ in support of the Ni[NiF₆] study. New data from refinements of X-ray powder diffraction of CoF₃ and IrF₃ are reported in the context of the distortion from hexagonal close packing of rhombohedral trifluorides.     

Acylzirconocene Chloride as an “Unmasked” Acyl Anion

Under mild conditions the acyl group of acylzirconocene chloride 1 formed from an alkene or alkyne and [(C₅H₅)₂ZrHCl] reacts as an “unmasked” acyl anion. The Lewis acid mediated reactions with aldehydes that yield α-ketol products in high yields demonstrate the versatility of this reagent for C–C coupling.     

Synthese und Kristallstruktur von [Se3N2Cl]+ GaCl4−

Synthesis and Crystal Structure of [Se₃N₂Cl]⁺GaCl₄^? [Se₃N₂Cl]⁺GaCl₄^? has been prepared by the reduction of [Se₂NCl₂]⁺GaC1₄^? with SbPh₃ in CH₂Cl₂ solution, forming red crystals, which were characterized by an X-ray structure determination. Space group P2₁/n, Z = 4, 1640 observed unique reflections, R = 0.050. Lattice dimensions at ? 80 °C: a = 929.4(1), b= 1078.8(1), c = 1135.7(1) pm, β = 92.026(9)°. The cations from nearly planar Se₃N₂ five membered rings with Se? N bond lengths from 170 to 176pm and a Se? Se bond of 242.2 pm. One of the selenium atoms is bonded to the chlorine atom.