The first aluminium-bridged [1.1]­ferrocenophane

The structure of the title compound, bis(μ-ferrocene-1,1′-diyl)­bis­[chloro(N,N,N′N′-tetra­methyl­ethyl­enedi­amine)­aluminium], [Al₂Fe₂Cl₂(C₅H₄)₄(C₆H₁₆N₂)₂], possesses a center of inversion and an anti conformation. Bound to each Al atom in the bridging position are one Cl atom and one mol­ecule of N,N,N′N′-tetra­methyl­ethyl­enedi­amine (TMEDA). The angle between the least-squares planes of the two cyclo­penta­dienyl (Cp) ligands is 3.6 (3)°. The five C atoms in the Cp rings are staggered on average at an angle of 10.3 (5)°.

1,4-Dimorpholino­benzene

In the crystal structure of the title compound, C₁₄H₂₀N₂O₂, there is a center of symmetry at the centroid of the benzene ring; the asymmetric unit is, therefore, one half molecule. The morpholine ring is in a chair conformation.

2,6-Bis(4-nitro­benzyl­idene)­cyclo­hexanone

In the crystal structure of the title compound, C₂₀H₁₆N₂O₅, the cyclo­hexane ring assumes the sofa conformation. Steric repulsions between one of the ortho-H atoms of each of the aryl groups and the equatorial H atoms at positions 3 and 5 of the cyclo­hexane ring lead to large torsion angles between the aryl rings and the adjacent olefinic linkages. Various bond angles confirm this steric impedance between the aryl and cyclo­hexane rings.

(E,E)-2-(4-Fluoro­phenyl­methyl­ene)-6-(4-nitro­phenyl­methyl­ene)cyclo­hexa­none

Both olefinic double bonds of the title compound, C₂₀H₁₆FNO₃, have the E configuration, while the cyclo­hex­yl ring adopts the sofa conformation. Non-bonded inter­actions occur between one of the ortho H atoms of each of the ar­yl rings and the equatorial H atoms at positions 3 and 5 of the alicyclic ring.

(E,E)-2-(4-Methyl­phenyl­methyl­ene)-6-(4-nitro­phenyl­methyl­ene)­cyclo­hexanone

Both olefinic bonds in the title compound, C₂₁H₁₉NO₃, possess an E configuration, while the cyclo­hexyl ring adopts a sofa conformation. The aryl rings are not coplanar with the adjacent olefinic groups due to non-bonded interactions between the ortho H atoms of the aryl rings and the equatorial H atoms at positions 3 and 5 of the cyclo­hexyl ring.

A monomeric fourfold-coordinated indium dihalide with an unusual coordination geometry

The single-crystal X-ray analysis of the title compound, {[dimeth­yl(2-pyrid­yl)sil­yl]bis­(trimethyl­silyl)meth­yl}diiodoindium(III), [In(C₁₄H₂₈NSi₃)I₂], revealed monomeric mol­ecules containing tetra­coordinated In with an unusual trigonal-pyramidal geometry.

The mono-(S)-α-methyl­benzyl­ammonium salt of (R)-homocitric lactone

The title salt, (S)-α-methyl­benzyl­ammonium (R)-2-carboxy­methyl-5-oxofuran-2-carboxyl­ate, C₈H₁₂N⁺·C₇H₇O₆⁻, was crystallized by resolution of a racemic mixture of lactones as the diastereomeric salt to separate the R anion, which is formed by the loss of a proton from the carboxylic acid group on the 2-position of the lactone ring. The crystal structure has a packing index of 69.5%, indicating very efficient packing.