Diversity of chain, interwoven and network structures formed by metal complexes with 2,3,5,6-tetrafluoro-1,4-bis(4-pyridyl-sulfenyl)benzene †

Abstract

The preparations are reported of a range of complexes formed by 2,3,5,6-tetrafluoro-1,4-bis(4-pyridylsulfenyl)benzene (L) with Mn II , Co II , Ni II , Zn II and Cd II , and single crystal X-ray diffraction studies have been made on four of the compounds. In the complex CoLI 2 ؒ0.5CH 2 Cl 2 , the organic ligand bridges tetrahedrally coordinated Co II centres so as to form chains. The compound Cd 2 L 3 (NO 3 ) 4 has a more complex structure in which sevencoordinate Cd centres are linked by two different types of L bridges so as to form arrays of 90-membered macrocycles comprising sheets of linked alternating enantiomeric helices. In the complexes MnL 2 (EtOH) 2 X 2 (X = Br or NCS), the bis(pyridyl) ligand utilises only one of its pyridyl units to coordinate directly to the metal atom. In both cases the Mn coordination environment comprises an all-trans octahedral arrangement of two anions, two ethanol ligands and two pyridyl units derived from two different L ligands. However in both compounds the non-coordinated pyridyl units bridge adjacent Mn centres by forming hydrogen bonds to the ethanol ligands. The resulting, complex networks are, however, dramatically different. The isothiocyanate complex forms sheets of partially interpenetrating helices whereas the bromide forms a system of triply interpenetrating (4,4) nets of 'over 2-under 2' type. X-and Q-Band EPR spectra of the manganese complexes are reported as are relevant spectroscopic results for the other complexes.

cis-Dibromobis(1,10-phenanthroline)manganese(II)

“…Compound (I) has expected values for bond lengths and angles. The dihedral angle between the two phenanthroline planes is 84.74 (6) and the average MnÐBr bond length is 2.535 (2) A Ê , within the range of previously reported values [2.496 (2) (Kienitz et al, 2000) and 2.677 (2) A Ê (Goodgame et al, 1999)]. There is a weak intermolecular interaction, C13Ð…”

Chains, Necklaces and Weaving Chain‐link Grids from Self‐Assembly Reactions

“…Interwoven structures for extended molecules have been reported on severalo ccasions [22] butt hey appear to have been largely serendipitous. In the case of polymeric {AuS À } n chains, the interweaving depends on the counter-ion presenta nd, in another case [22c] where ah elical structure similart o{ [Cu(2) 2 ] [Cu 2 (piv) 4 ] 2 + } n was reported, the intertwined structure was only one of the polymorphs observed, and not ap articularly stable one.…”

Anion Template Effect and the Polymerization Degree – Diversity through Flexibility

“…[14] The threefold parallel interpenetration of two-dimensional 4,4 nets is already known. [15][16][17][18] However, the mode of interpenetration of M1 is previously unpresented. This mode is due to the use of the flexible tetradentate ligand which provides new geometrical possibilities for the network.…”