Winfried Hinrichs

Koordinationsverhältnisse in basenfreien tricyclopentadienyl-lanthanoid(III)-komplexen: I. Röntgenstrukturanalyse von tricyclopentadienyl-praseodym(III)

Abstract A single crystal X-ray analysis of sublimated Cp 3 Pr III confirms a singular polymeric chain structure involving η 5 -coordination of each Pr III ion with three close-lying Cp ligands and η 2 -coordination with a fourth, bridging Cp ligand (formal coordination number: 11, space group: P 2 1 , lattice parameters: a 831.4; b 971.4, c 837.2 pm; β 116.06°). The crystal structure of Cp 3 Pr differs markedly from that reported in 1969 for the similar polymeric samarium complex; on the other hand, some interesting features (concerning the crystallographic parameters, the MC distances and the formal coordination number) in accordance with the recently published structure of polymeric (C 5 H 4 CH 3 ) 2 Yb II . (OC 4 H 8 ) are apparent.

Koordinationsverhältnisse in basenfreien tricyclopentadienyl-lanthanoid(III)-komplexen: IV. Die röntgenstrukturen von tricyclopentadienyl-erbium(III) und -thulium(III)☆

Abstract The single crystal X-ray analyses of sublimated (C5H5)3Er (6) and (C5H5)3Tm (7) confirm, for the first time, the existence of coordinatively well-saturated molecules containing just three η5-C5H5 ligands per metal ion (formal coordination number: 9, space group: Pna21, lattice parameters: a 1972.1(3), b 1389.4(1), c 862.4(3) pm for 6, and a 1999.1(3), b 1379.8(4), c 1379.8(4), c 857.8(3) pm for 7; R = 0.076 and 0.047, respectively). Individual molecules align themselves into chains by Van der Waals interactions. The structures of 6 and 7 show a marked contrast to those of their La und Pr homologues on the one hand, and with the structure of (C5H5)3Lu on the other.

Structure and electrical conductivity of TCNQ-2,3,7,8-tetramethoxychalcogenanthrene complexes

Abstract Charge-transfer complexes formed by reaction of 2,3,7,8-tetramethoxychalcogenanthrenes(5,10-dichalcogenacyclo-diveratrylenes, ‘Vn 2 E 2 ’) with 7,7,8,8-tetracyanoquinodimethane (TCNQ) are prepared and their structures determined. Spin concentration, mobilities and gap energies of the polycrystalline samples are evaluated from e.s.r. intensities and electrical conductivity measurements. The influence of the different chalcogen atoms on physical properties is discussed.

SELFSTACKING SYSTEMS, PART 6.1 HOST LATTICE FUNCTION OF 2,3,8,9-TETRAMETHOXYDIBENZO[c,e][1,2]-DICHALCOGENINS IN THEIR ELECTRICALLY CONDUCTING IODINE COMPLEXES

Abstract The structures of 2,3,8,9-tetramethoxydibenzo[c,e][1,2]dithiin (o-S2, 1) and -diselenin (o-Sc2, 3) have been determined hy single-crystal X-ray diffraction methods. Both compounds have a columnar structure in which the orientation of the molecules alternates with respect to their dichalcogeno bridges. The same kind of slacks had been found before in the electrically conducting iodine complex [o-S2]1 1.16 (2) with channels parallel to the stacks in which chains of disordered polyiodide ions are intercalated, i,e. the host lattice of 2 is performed in 1. o-Se2-(3) also forms an iodine complex of composition [o-Se2]1, (x = 1.5–2.5) (4) which is, however, thermally unstable loosing iodine already at room temperature. For reasons of comparison the X-ray structure of 3,3′,4,4′-tetramethoxybiphenyl (5) has also been determined.

Cyclic ligands with fixed co-ordination geometry. Part 6(1). Chalcogenanthrenes as bridging ligands in dinuclear complexes of rhenium(I) and platinum(IV)-X-ray crystal structure of di(μ-chloro) (μ-2, 3, 7, 8-tetramethoxyselenanthrene) hexamethyl diplatinum(IV)

SummaryThe chalcogenanthrenes Vn2EE′; 2, 3, 7, 8-tetramethoxythianthrene (E=E′=S), 2, 3, 7, 8-tetramethoxydibenzothiaselenin (E=S, E′=Se), and 2, 3, 7, 8-tetramethoxyselenanthrene (E=E′=Se), react with [{ReBr(CO)3(THF)}2] and [{PtXMe3}4] (X=Cl or Br) to give the dinuclear complexes [(fac-L3M)2(μ-X)2 (μ-Vn2EE′)] (M=Re, L=CO, X=Br; M=Pt, L=Me, X=Cl or Br) in which the chalcogenanthrenes reveal a hitherto unknown co-ordination mode as bridging ligands. Telluranthrene (Pn2 Te2), however, forms mononuclear complexes of compositionfac-[L3MX(Pn2Te2)] (M=Re, L=CO, X=Br; M=Pt, L=Me, X=Br) with a chelating chalcogenanthrene ligand. Whereas the rhenium compounds are not stable enough in solution to be studied by i.r. spectroscopy, the platinum compounds can be well characterised by their1H n.m.r. spectra. Furthermore, the results of a single-crystal structure determination of [Pt2Cl2Me6(Vn2Se2)] are reported. The Pt−Se distance of 259 pm indicates a relatively weak interaction between the chalcogenanthrene and the remaining dinuclear fragment of the molecule.

Cyclic ligands with fixed coordination geometry. Part 7 Cationic copper(I) complexes of composition [Cu(Vn3S3)L]+-CF3SO3- (Vn3S3=5,10, 15-trithia-cyclo-triveratrylene, L=CO, CH3OH)

SummaryCopper(I) trifluoromethanesulphonate and 5, 10, 15-trithia-cyclo-triveratrylene (Vn3S3, 3) react with CO in CHCl3 as solvent to yield a carbonyl complex which can be crystallised from EtOH in a CO atmosphere giving the complex [Cu(Vn3S3)(CO)]O3SCF3·0.5 EtOH (8), which was characterised by av(CO) absorption band at 2140 cm−1 indicating a weak back donation of copper(I). When (8) is heated in MeOH in an N2 atmosphere, complex [Cu(Vn3S3)(CH3OH)]O3SCF3·MeOH (15) is formed. X-ray analysis of (15) reveals a distorted tetrahedral coordination of the copper(I) ion with a strongly bonded methanol ligand (Cu−O 198 pm, Cu−S 229 pm).

Selbststapelnde Systeme, I 4,4′,5,5′-Tetramethoxy-2,2′-dithiobiphenyl-Iod (6/7), eine Verbindung mit Radikalkationen und Polyiodidketten / Selfstacking Systems, I 4,4′5,5′-Tetramethoxy-2,2′-dithiobiphenyl-Iodine (6/7), a Compound with Radical Cations and Polyiodide Chains

The title compound can be isolated from concentrated solutions of 4,4′,5,5′-tetramethoxy-2,2′- dithiobiphenyl (DTB, 2) and iodine as blue needles with brass-coloured luster. The crystal structure consists of stacks of (partially oxidized) DTB units with alternating orientations and of disordered polyiodide chains in channels between these stacks. The DTB molecule is not planar; the dihedral angle between the two phenyl rings is 25.1°, the dithio bridge is inclined by 41.7° to the longitudinal axis. The bond distances and angles of the disulfide group are in the normal range, the dihedral angles (CArSS′CAr′ = 55.6°, CArCArSS′ = 41.3°) differ from the ideal values of ca. 90° as a consequence of the cyclic structure