Arene-perfluoroarene interactions in crystal engineering. XV. Ferrocene-decafluorobiphenyl (1/1)

The title crystal, [Fe(C5H5)2]·C12F10, comprises infinite chains of alternating component mol­ecules, linked through face-to-face contacts of nearly parallel cyclo­penta­dienyl and penta­fluoro­phenyl rings. The deca­fluoro­biphenyl mol­ecule has a crystallographic twofold axis and the Fe atom of the ferrocene mol­ecule is on a crystallographic inversion centre, with both cyclo­penta­dienyl rings disordered

Arene-perfluoroarene interactions in crystal engineering. Part 14. 1 : 1 Complexes of octafluoronaphthalene with fluorene and 9,10-dihydrophenanthrene

The 1:1 molecular complexes of octafluoronaphthalene (OFN) with fluorene (1) and with 9,10-dihydrophenanthrene (2) were prepared by cocrystallization of the components and characterized by single-crystal X-ray diffraction. The structure of 1 can be described as a mixed-stack or a laminar checkerboard motif of alternating OFN and fluorene molecules, whilst slanted mixed-stack, herringbone, and face-to-face heteromolecular dimer motifs can all be recognised in 2.Key words: single crystal, X-ray structure, π stacking, fluoroarene

Arene-perfluoroarene interactions in crystal engineering. Part 3. Single-crystal structures of 1 : 1 complexes of octafluoronaphthalene with fused-ring polyaromatic hydrocarbons

Molecular complexes of 1:1 stoichiometry of octafluoronaphthalene (OFN) with the polyaromatic hydrocarbons anthracene, phenanthrene, pyrene and triphenylene have been prepared, and their single-crystal X-ray structures determined at 120 K. All of the structures are composed of infinite stacks of alternating, almost parallel molecules of OFN and the hydrocarbons, in contrast to the herringbone or c-type (flattened herringbone) packing of the pure components. It is clearly shown that the stacking motif does not require a close correlation between the molecular geometry of the arene and perfluoroarene species, but is stable over a wide range of differing sizes and shapes. Thus, the arene-perfluoroarene interaction is of general importance as a supramolecular synthon. The molecular geometries of the components are not affected by complexation, indicating the absence of charge transfer in the complexes. The role of close C-H . . .F-C and C-F . . .F-C intermolecular contacts between stacks is discussed. A re-determination of the single-crystal structure of triphenylene at 150 K is also reported, providing a more accurate comparison with that of the 1:1 OFN . triphenylene complex

Arene-perfluoroarene interactions in crystal engineering 8: structures of 1 : 1 complexes of hexafluorobenzene with fused-ring polyaromatic hydrocarbons

A series of 1:1 complexes of hexafluorobenzene (HFB) with naphthalene, anthracene, phenanthrene, pyrene and triphenylene were prepared and their X-ray crystal structures determined at low temperatures. Each structure contains infinite mixed stacks of alternating nearly-parallel molecules of HFB and arene, which display various slip distortions and form different 3-dimensional motifs. The naphthalene, anthracene and pyrene complexes show polymorphism. Crystal packing of HFB complexes is compared with that of corresponding octafluoronaphthalene complexes. Ab initio DFT calculations on the infinite lattices give lattice parameters and slip parameters in close agreement with the experimental crystal structures, while showing that intermolecular cohesion is predominantly of electrostatic, rather than van der Waals, origin

Crystal engineering with ethynylbenzenes Part 2. Structures of 4-trimethylsilylethynyl-N,N-dimethylaniline, and 4-ethynyl-N,N-dimethylaniline with Z '=12 and a single-crystal to single-crystal phase transition at 122.5 +/- 2 K

The crystal and molecular structures of 4-ethynyl-N,N-dimethylaniline (1), and 4-(trimethylsilylethynyl)-N,N-dimethylaniline (2), have been obtained from X-ray diffraction data. Crystals of 1 exhibit a phase transition at 122.5 ± 2 K. Both polymorphs are triclinic with Z′ = 12, and the molecules are linked into dodecamers by weak hydrogen bonds involving [triple bond, length as m-dash]C–H groups. The orthorhombic crystals of 2 show no phase changes and have Z′ = 1.5 (3 half molecules) without short intermolecular contacts