Olli Orama

Reaktionen von komplexliganden: XXIV. synthese von naphthol-derivaten aus carbonyl-carben-komplexen und alkinen: regioselektiver einbau des alkins in das napththalin-gerüst

Zusammenfassung Pentacarbonyl(methoxyphenylcarbene)chromium reacts with various alkynes to give tricarbonyl(4-methoxy-1-naphthol)chromium complexes. Aliphatic n-1-alkynes yield regiospecifically 2-alkylnaphthol compounds; 2-alkynes, however, lead to mixtures of 2,3-dialkylnaphthol derivatives, with the 3-methyl isomers as major products. With diarylacetylenes the regioselectivity of the incorporation of the alkyne is practically lost. The ratios of the isomers are determined on the basis of 1H NMR spectroscopy using the tricarbonylchromium complexes and, in part, the uncoordinated naphthols. The structure of 3-p-trifluormethylphenyl-4-methoxy-2-p-tolyl-1-naphthol is determined by X-ray spectroscopy.

Pentacarbonylmetallderivatevon phosphinidenen und diphosphenen

Abstract Reaction of Na 2 [M 2 CO 10 ] (M = Cr, Mo, W) with RPCl 2 (R = mesityl, CH(SiMe 3 ) 2 ) yields, depending on the reaction conditions as well as on the steric demand of R, phosphinidene compounds [(CO) 5 M] 2 PR and diphosphene species [(CO) 5 M] n RPPR ( n = 1, 2). With especially bulky substituents mono-nuclear diphosphene derivatives are the preferred reaction products. For dinuclear diphosphene compounds the Z -configuration is induced when R = mesityl while in other cases the E -configuration is the more stable form. The structures of the new compounds are documented by X-ray analyses of three examples. The accumulated material allows for a comparative discussion of the 31 P NMR spectra, which often show unconventional low-field shifts (up to 1216 ppm), as well as of the characteristic UV/VIS spectra. For all compounds IR, 1 H NMR and mass spectra as well as correct analyses are presented.

μ3-P- und μ3-As-verbrückte cluster als liganden

Abstract The trihalophosphane complexes LnMPHal3 (LnM = Cp(CO)2Mn, (CO)5Cr, (CO)5W; Hal = Cl, Br), upon treatment with Co2(CO)8, mainly yield clusters of the type Co3(CO)9(μ4-P)MLn with the (μ3-P)Co3(CO)9) unit acting as ligand. The analogous arsenic compound Co3(CO)9(μ4-As)Cr(CO)5 is obtained from the arsinidine complex [(CO)5Cr]2AsCl with NaCo(CO)4. In addition to the syntheses and reactios of these clusters several reactions leading to clusters with μ4-P-, μ4-As-, μ4-PR- and μ2-PR2 groups by reductive dehalogenation of coordinated halophosphanes are reported. The different types of compounds are documented by six X-ray-structure analyses.

Diphosphor, phosphor-, arsen- und antimonatome als clusterbaugruppen

Abstract Reactions of Fe2(CO)9 with LnMPHal3 (LnM = 16-electron fragment: Cp(CO)2Mn, (CO)5Cr, (CO)5Mo, (CO)5W) yield clusters of the type F3(CO)9(μ4-P)2(MLn)2 (II). Compounds II contain the trigonal bipyramidal cluster framework Fe3(CO)9(μ3-P)2, the basis of which is a closed triangle formed by three Fe(CO)3 units; the apical positions of the trigonal bipyramid are occupied by phosphorus atoms. Each of the capping phosphorus atoms binds an additional MLn fragment. Compounds of type II are also obtained from Fe2(CO)6(μ3-P)2(MLn)2 (I) by formal addition of an Fe(CO)3 group. A further general synthetic approach to clusters Fe3(CO)9(μ4-X)2 (MLn)2 (X = P, As, Sb) is the reaction of halo-phosphinidene, arsinidene or stibinidene complexes, (LnM)2XHal (X = P, As, Sb) with Na2Fe(CO)4. Similar procedures are used for the construction of compounds III and IV. Complexes III contain phosphorus as a μ4-spiro centre; compounds IV contain metallacyclic phosphanes (CO)4 FeP(R)Fe (CO)4 as ligands. From (CO)5CrPBr3 and Fe2(CO)9 the cluster Fe2(CO)7(PP)[Cr(CO)5]2 (V) is obtained in which a diphosphorus unit is side-on and end-on coordinated as an eight-electron ligand. The identity of the new compounds is documented by analytic and spectroscopic data as well as by X-ray-structure analyses of seven compounds.

Bis(diphenylphosphino)acetylene complexes of Cp(CO)2Mn and (CO)5M(M = Cr, W)

Abstract Bis(diphenylphosphino)acetylene (DPPA) react with THF complexes of Cp(CO) 2 Mn and (CO) 5 M (M = Cr, W) to yield binuclear disphosphine-bridged complexes of type [CP(CO) 2 Mn] 2 DPPA and [(CO) 5 M] 2 DPPA. A mononuclear complex Cp(CO) 2 MnDPPA can be isolated when a sol1 1 molar ratio of the reactants is used. The preparation and characterisation of Cp(CO) 2 MnDPPA, [Cp(CO) 2 Mn] 2 DPPA, [(CO) 5 Cr] 2 DPPA and [(CO) 5 W] 2 DPPA are reported, as is the crystal structure of [Cp(CO) 2 Mn] 2 DPPA determined by X-ray diffraction.

Reaktionen des diphosphen-komplexes (CO)5CrPhPPPhCr(CO)5

Abstract The diphosphene compound [(CO) 5 Cr] 2 PhPPPh (II), which is formed from [(CO) 5 Cr] 3 PhPPPh (I) at 70°C, reacts with HX (X = OH, OMe, NHBu, Cl) to give the diphosphane species [(CO) 5 Cr] 2 PhP(H)-(X)PPh (III) with complete threoselectivity. Addition of Br 2 to II leads to a mixture of both diastereoisomeric forms of [(CO) 5 Cr] 2 PhP(Br)(Br)PPh (IV). Sulfur adds in an erythro-selective 2+1- cycloaddition, yielding the thiadiphosphirane compound Va. Similarly, CH 2 N 2 gives the diphosphirane complex Vb. 2 + 4-Cycloadditions of cyclopentadiene or 2,3-dimethylbutadiene lead to the expected Diels-Alder type addition products VI. The novel compounds have been characterized by analytical and spectroscopic data as well as five X-ray structural analyses.

Darstellung dreigliedriger phosphorhaltiger ringliganden aus phosphiniden- und diphosphen-komplexen ☆

Abstract Diphosphene derivatives RPPR[Cr(CO)5]3 undergo formal [2 + 1] cycloadditions at the PP double bond yielding compounds containing three-membered cyclic ligands with PPP , PPN or PPS frameworks. Three-membered rings with CCP frameworks are obtained by trapping LnMPR with olefins. The synthesis and properties of M(CO)5 derivatives of these cyclic ligands as well as X-ray analyses of R PCH 2 C H2(W(CO)5] and (RP)3[Cr(CO)5]2 are described.

Transformationen von Clustern mit dem (μ3-RP)Fe3(CO)9-Gerüst. Synthese und Reaktionen von ([μ3-RP)Fe3(CO)9]2−

Abstract The clusters (μ3-RP)Fe3(CO)10 (1) or (μ3-RP)Fe3(CO)9(μ2-H)2 (2) can reversibly be transformed into the cluster anions [(μ3-RP)Fe3(CO)9 (μ2-H)]− (3) and [(μ3-RP)Fe3(CO)9]2− (4). The pyrophoric clusters 4 react with the divalent electrophile CH2I2 to give the complexes (μ3-η2-RP=CH2)Fe3(CO)10 (5), which contain a cluster-stabilized phosphaalkene, RP=CH2, as a ligand. With monovalent electrophiles R′X, such as Me2SO4, compound 4 (R = anisyl), yields, upon protolytic work-up, the complexes (μ3-η3-R′P-anisyl)Fe3(CO)9(μ2-H) (6) in which the phosphorus-bound aryl residue of the μ2-bridging phosphide ligand (R′P-anisyl) forms an η2-coordination to the third iron atom of the cluster. The η2-coordination of the aryl substituent may be reversibly released by two-electron ligands L under formation of (μ2-R′P-anisyl)(μ2-H)Fe3(CO)9L (7). In addition, the transformation sequence of 5 into 6 is accomplished by an H−, H+ addition sequence. The experiments are documented by analytic and spectroscopic data as well as by X-ray analyses.

The crystal structure of a heteronuclear Pt22CuL4 complex of 1-methyluracil, Cu[Pt(NH3)2(C5H5N2O2)2]2SO4·8H2O

Abstract The crystal structure of heteronuclear bis[bis(μ- 1-methyluracilato- N 3, O 4)- cis -diammineplatinum(II)]- copper(II) sulfate octahydrate, Cu[Pt(NH 3 ) 2 (C 5 H 5 - N 2 O 2 ) 2 ] 2 SO 4 ·8H 2 O, has been determined by X-ray diffraction. The compound crystallizes in space group I 4 1 / a with cell parameters a = 20.470(7), c = 23.509(8) A, V = 9850(6) A 3 , Z = 8. The structure was refined on 2783 reflections to R = 0.045 and R w = 0.064. The deprotonated 1-methyluracilato ligand coordinates to cis -Pt(NH 3 )2 2+ , by N3 and to Cu by O4. Both the Pt and Cu have square-planar coordination spheres with Cu in the inversion center of the trinuclear Pt 2 Cu unit. The PtCu distances within the cation are 2.684(1) A. The non- coordinating O2 oxygens take part in a hydrogen bond network with NII 3 groups of the adjacent molecular cations.

Übergangsmetallketen-verbindungen: XXIII. Röntgenstrukturanalyse von α-[Dicarbonyl(η5-cyclopentadienyl)trimethylphosphinwolframa]α-(4-methylphenyl)essigsäuremethylester

Abstract Transition-metal-substituted η 1 -ketenes react with methanol to form methyl acetate with the metal in the α-position. X-Ray analysis proves the trans -position of the two carbonyl ligands.