Inclusion of tetramethylpyrazine in channels of the organic zeolite 2,4,6-tris(4-bromophenoxy)-1,3,5-triazine

2,4,6-tris(4-bromophenoxy)-1,3,5-triazine (BrPOT) features a channel size (11-12Å) allowing the inclusion of large guest molecules such as tetramethylpyrazine (TMPZ). TMPZ forms π-stacks (d: 3.5Å) along channels of BrPOT and shows rotational disorder for methyl positions. Co-inclusions of I2 resulted in a doped state where I2 molecules are oriented perpendicular to the channel axis with positional disorder as well. The particular orientation of I2 molecules is evident from the observed dichrois

Novel Host-Guest Structures of 2,4,6- Tris (4-Halophenoxy)-1,3,5-Triazines(XPOT): Inclusion of C60 and Pyridine

The crystal structures of two halophenoxytriazine host-guest compounds are reported and discussed. They feature inclusion of C60 into cages of 2,4,6-tris(4-iodophenoxy)-1,3,5-triazine [IPOT, hexagonal, P63/m, a=16.367(2)Å, c=20.661(4)Å, V=4793.1(13)Å3, Z=2] and of pyridine6-clusters into cages of 2,4,6-tris(4-bromophenoxy)-1,3,5-triazine (BrPOT, rhombohedral, R $$\bar{3}$$ , a=15.5186(8)Å, c=39.521(3)Å, V=8242.7(8)Å3, Z=6). The stackings of the threefold symmetric layers of XPOT host molecules are different from each other and from those of all previously reported XPOT inclusion compounds (X: Cl, Br, I). Graphical Abstract: The new compounds IPOT3·C60 and BrPOT2·py3, represent new packing types in the family of threefold symmetric XPOT inclusion compounds (XPOT=2,4,6-tris(4-halophenoxy)-1,3,5-triazine; X=Cl, Br, I

Piano-stool iron(ii) complexes as probes for the bonding of n-heterocyclic carbenes: indications for -acceptor ability

A series of new piano-stool iron(II) complexes comprising mono- and bidentate chelating N-heterocyclic carbene ligands [Fe(cp)(CO)(NHC)(L)]X have been prepared and analyzed by spectroscopic, electrochemical, crystallographic, and theoretical methods. Selectively substituting the L site with a series of ligands going from carbene to pyridine to CO suggests that CO is the strongest π acceptor, while the behavior of pyridine and carbene is nearly identical. This suggests that in these complexes comprising an electron-rich iron(cp)(carbene) fragment, N-heterocyclic carbenes are not pure σ donors but also moderate π acceptors. Theoretical calculations support this bonding model and indicate charge saturation at the metal as key for π back-bonding to N-heterocyclic carbenes. On the basis of voltammetric measurements, the Lever electrochemical parameter of these carbenes has been determined: EL = +0.29. Systematic substitution of the wingtip groups of the carbene revealed only subtle changes in the electronic properties of the iron center, thus providing a suitable methodology for ligand-induced fine-tuning of the coordinated metal

Syntheses, characterization and crystal structures of a new functionalised TTF derivative and its Ni(II) complex

The new ligand 4,5-bis (2-pyridylmethylsulfanyl)-4',5'-bis(cyanoethylthio)tetrathiafulvalene (BPM-BCET-TTF) and its nickel(II) complex have been prepared and crystallographically characterized. The Ni(II) complex shows octahedral geometry around the metal ion with the coordination site occupied by the pyridyl nitrogen atoms, the thioether sulfur atoms of the ligand and cis coordination of the halide ions

Stereoselective synthesis of cyclometalated iridium(III) complexes: characterization and photophysical properties

The stereoselective synthesis of a highly luminescent neutral Ir(III) complex comprising two bidentate chiral, cyclometalating phenylpyridine derivatives, and one acetylacetonate as ligands is described. The final complex and some intermediates were characterized by X-ray structural analysis, NMR-, CD-, and CPL-spectroscopy