Norman C. Baenziger

Crystal Structure and Molecular Motion of Solid Carbon Disulfide

The crystal structure of CS2 was determined at two temperatures from intensity data measured with a proportional counter and a modified Weissenberg apparatus. The orthorhombic cell [(a) 6.3437(8), (b) 5.5244(4), (c) 8.9971(7), 143°K, Cmca, Z = 4] exhibited marked anisotropic thermal expansion, the coefficients of thermal expansion being αa = 630 × 10−6 °C−1, αb = 570 × 10−6 °C−1, αc = −630 × 10−6 °C−1. Positional and anisotropic thermal parameters were refined using upper‐angle data (sinθ / λ ≥ 0.35) and the x‐ray results were compared with data from spectroscopic sources on the molecular motion of CS2 in the solid. The unweighted reliability indices for the two refinements were 0.039 (148°K) and 0.056 (133°K). The carbon–sulfur bond length corrected for foreshortening due to libration was 1.560(3) A (133°K) and 1.559 A (148°K), in agreement with calculations of the length in the gas from spectral data (1.558 ± 0.0005) and electron diffraction (1.559 ± 0.002).

A new class of reactive, transition metal–metal doubly-bonded organodimetallic complexes: synthesis, structure, and reactivity of (η-C5Me4R)2Ta2(µ-X)4(R = Me, Et; X = Cl, Br)

Reduction of (η-C5Me4R)TaX4(R = Me, Et; X = Cl, Br) with two equivalents of sodium amalgam in toluene affords the reactive tantalum–tantalum doubly-bonded species (η-C5Me4R)2Ta2(µ-X)4 in 70% yield; the solid-state structure of (C5Me5)2Ta2(µ-Br)4 consists of a TaTa double bond, 2.748(2)A in length, bridged symmetrically by four bromide ligands.

Butatriene formation via CuBr-induced self coupling of an α-bromo vinyl zinc reagent: synthesis and X-ray structure of Z-1,1,1,6,6,6-hexafluoro-2,5-diphenylhexa-2,3,4-triene

Title cumulenes 2a and 2b were prepared by reaction of CF3(Ph)CC(Br)ZnX [X = Br, CF3(Ph)CCBr–]1 with CuBr, or by oxidative coupling of 1 with FeCl3 to form 2a,b and [CF3(Ph)CCBr–]23, which can be dehalogenated with zinc to afford 2a,b; the cumulene isomers are readily separated by silica-gel chromatography, and may be prepared in good yield on a multi-gram scale.

Dammara-20,25-dien-3β,24α-diol: A natural repellent of Acromyrmex octospinosus

Abstract Dammara-20,25-dien-3β,24α-diol was isolated from the hexane extract of Abuta racemosa , characterized by NMR spectroscopy and single crystal diffraction analysis, and shown to be a natural repellent of an attine ant.

X-Ray crystal structure of bis(tetraethylammonium)di-µ-thio-[bis(phenylthio)ferrate(III)[dithiomolybdate(V)], [Et4N]2[(PhS)2FeMoS4]: a dinuclear complex with the FeMoS2 core

An X-ray crystallographic investigation shows that the dinuclear anion [(PhS)2FeMoS4]2– consists of two edge-sharing MS4 tetrahedra (M = Mo and Fe) and the FeS2Mo planar unit.

Tri­benzyl(η5-penta­methyl­cyclo­penta­dienyl)­hafnium(IV)

The title compound, [Hf(C7H7)3(C10H15)], adopts a monomeric three-legged piano-stool structure. One benzyl ligand is disordered between two sites (44:56%) related by a ∼30° rotation about an axis defined by the Hf atom and the ipso-C atom of the benzyl ligand.

Synthesis and X-ray structure of bis(trifluoromethyl)(N,N-diethyldithiocarbamato)-copper; a remarkably stable perfluoroalkylcopper(III) complex

The reaction between trifluoromethylcadmium reagent and Br2Cu(edtc)(edtc =N,N-diethyldithiocarbamato) or CdI+[(CF3)2Cu]– with [Et2NC(S)S]2 in DMF (dimethylformamide) at –30°C yields the stable CuIII perfluoroalkylcopper complex, (CF3)2CuSC(S)NEt2.

Di-2-pyridyl ketone 2-pyridylhydrazone, C16H13N5

Mr= 275.34, orthorhombic, P21212 ~, a= 7.9213 (13), b = 10.603 (3), c= 16.499 (2) A, V= 1386 A a, Z= 4, D m= 1.304 (10), D x= 1.320g cm -3 MoKa, 2=0.7107 A, /~=0.91 cm -), F(000)=