Eva Maria Peters

Über Reaktionen mit Betainen, 17. Mitt. Synthese und Kristallstruktur von Pyridinium-di-trihalogenacyl-methyliden

The crystal structures of pyridinium-di-trifluoroacethyl-methylide and the trichloro analog (2 a and2 b) have been determined by means of X-ray structure analyses. The synthesis of the monohalogenoacetyl derivatives4 a and4 b from the hydrobromides3 a and3 b is described.

Synthese, Struktur und Reaktivität labiler Rhodium(I)-Komplexe mit iPr2PC2H4NMe2 und iPr2PC2H4OMe als Phosphanliganden / Synthesis, Structure and Reactivity of Labile Rhodium(I) Complexes Containing iPr2PC2H4NMe2 and iPr2PC2H4OMe as Phosphine Ligands

Square-planar rhodium(I) complexes [RhCl(iPr2PC2H4Y)2] (8, 9) containing one chelating and one P-bonded monodentate phosphine ligand are prepared from [RhCl(C8H14)2]2 (7) and the new functionalized phosphines iPr2PC2H4Y (5,6). Reaction of 9 (Y = NMe2) with CO and of 8 (Y = OMe) with CO, C2H4, C2H2, C2Ph2 and HC2Ph leads to opening of the chelate ring and formation of the complexes trans-[RhCl(L)(η1-P–iPr2PC2H4Y)2] (10-15). Treatment of 8 with H2 gives the dihydridorhodium(III) compound [RhH2Cl(iPr2PC2H4OMe)2] (16). The vinylidene complexes trans-[RhCl(=C=CHR)(η1-P– iPr2PC2H4OMe)2] (17, 18) are obtained by thermal or pyridine promoted rearrangement of 13 (L = C2H2) and 15 (L = HC2Ph). 13 and 15 have also been used as starting materials for the synthesis of the cyclopentadienyl alkyne and vinylidene complexes 19-21. The X-ray crystal structure of the parent compound 8 was determined.

Eindimensionale Kupfer(II)-Koordinationspolymere: Kristall-Engineering durch variable Verknüpfungsmuster [1] / One Dimensional Copper(II) Coordination Polymers: Crystal Engineering through Variable Types of Linkage [1]

Reaction of a methanolic copper(II) acetate solution with tetrazolyl enol derivatives 2a or 2b leads to the formation of the corresponding lD-coordination polymer 1∞[CuL2] 3a and pseudo 1D-coordination polymer [CuL2]2 3b, respectively. On the contrary, reaction of 2c with methanolic copper(II) acetate solution yields OH-bridged 1D-coordination polymer 1∞[CuL2(MeOH)2 3c. Single-crystal X-ray diffraction of the supramolecular species 3 established unequivocally the structures of the stairlike coordination compounds. Reaction of a methanolic copper(II) acetate solution with amidotetrazole derivative 6 leads to the formation of the lD-coordination polymer 1∞ [CuL2] 7. The structure of 7 has been established by X-ray structure analysis

UNUSUAL CONVERSIONS OF A ZWITTERIONIC POLYFUSED TRIAZINE WITH ELECTRON-DEFICIENT DIENOPHILES

Investigation of reactions of the zwitterionic polycycle 1 with electron-deficient dienophiles revealed that Michael addition products 3 and 4, selective cycloadducts 2 and, in a special case, a stable dimeric radical cation 5 are formed.

Synthesis and Characterisation of Na5[CoO2]CO3

Na5[CoO2]CO3 was prepared via the azide/nitrate route. Stoichiometric mixtures of the precursors (Co3O4, NaN3, NaNO3 and Na2CO3) were heated in a special regime up to 500 °C and annealed at this temperature for 50 h in silver crucibles. Single crystals have been grown by subsequent annealing of the powder at 500 °C for 2000 h in silver crucibles, which were sealed in glass ampoules under dry Ar. According to the X-ray analysis of the crystal structure (P4/mmm, Z = 1, a = 4.6467(4), c = 8.2577(6) Å ). Na5[CoO2]CO3 is isostructural with Na5[NiO2]CO3 and contains Co1+, which is coordinated by two oxygen atoms forming a dumb-bell. Na5CoCO5 decomposes at 600 °C to Na3CoO2 and Na2CO3.