Agnieszka Łapczuk-Krygier

The crystal structure of (1RS,4RS,5RS,6SR)-5-cyano-5-nitro-6-phenyl-bicyclo[2.2.1]hept-2-ene

Structure of nitronorbornene derivative C14H12N2O2 synthesized in the reaction of cyclopentadiene with E-2-phenyl-1-cyano-1-nitroethene was determined by single crystal X-ray diffraction analysis. It was found that in analyzed molecule the nitro group is in endo-position whereas phenyl group have exo-orientation.

2,4-Bis[bis(diisopropyl-amino)-phos-phanyl]-1,2,3,4-tetra-phospha-bicyclo[1.1.0]butane.

The title compound, C24H56N4P6 or (iPr2N)2P–P4–P(NiPr2)2, adopts a butterfly structure, with planar environments for the N atoms and pyramidal environments for the P atoms. The structure studied has a 15% twin component that is related by a twofold rotation about [100].

Regiospecific formation of the nitromethyl-substituted 3-phenyl-4,5-dihydroisoxazole via [3 + 2] cycloaddition

Abstract5-(Nitromethyl)-3-phenyl-4,5-dihydroisoxazole was obtained as a product of a high-yielding [3 + 2] cycloaddition reaction of in situ-generated benzonitrile N-oxide and 3-nitroprop-1-ene. For the first time, the regiochemistry of this reaction was unambiguously proven by X-ray structural analysis. The quantum-chemical calculation performed at the M06-2X/6-31G(d) (PCM) theoretical level affords a basis for explaining the course of reaction as well as the nature of transition states. Next, further DFT calculations together with spectral data shed light on structural aspects of the product.Graphical abstract

Chlorido(η-cyclo-penta-dien-yl)[(4a,4b,8a,9,9a-η)-fluoren-yl](fluorenyl-κC)zirconium(IV) toluene solvate.

In the title compound, [Zr(C5H5)(C13H9)2Cl]·C7H8, the ZrIV atom is coordinated by a Cl atom, a cyclopentadienyl (Cp) ligand [Zr–centroid (Cp) = 2.199 (3) Å] and two fluorenyl ligands (Fl) [Zr–centroid (Fl) = 2.273 (2) Å and Zr—CH from fluorenyl = 2.355 (2) Å] in a distorted tetragonal geometry. The dihedral angles between the mean planes of the fluorenyl ring systems and the Cp ring are 36.62 (6)° for the η1-coordinated fluorenyl and 52.85 (6)° for the η5-coordinated fluorenyl, while the dihedral angle between the mean planes of the two fluorenyl ring systems is 76.18 (7)°.