Search results for "organometalli"
showing 10 items of 395 documents
Complexes of organometallic compounds
1974
Abstract Novel complexes RClSntrid, where R is Me, Ph, n-Oct, and trid 2− are dianions of tridentate “planar” ligands with ONO and SNO donor atoms, were synthesized and investigated in the solid state by infrared and Mossbauer spectroscopy. Possible configurations are discussed; polymeric trigonal bipyramidal structures seem to occur, although five-coordinated monomers as well as octahedral dimers (via oxygen or sulfur bridges) are not excluded.
Bioconjugates of 1’-Aminoferrocene-1-carboxylic Acid with (S)-3-Amino-2-methylpropanoic Acid and L-Alanine
2010
Formal CH 2 insertion in bioconjugates composed of 1'-aminoferrocene-1-carboxylic acid (Fca) and alanine Boc-Ala-Fca-Ala-OCH 3 gives Fca bioconjugates with the β-amino acid (S)-3-amino-2-methylpropanoic acid (Aib). The novel homologous conjugates of ferrocene were fully characterized by spectroscopic and analytical methods. NMR, CD and IR spectroscopy in concert with DFT calculations suggest that the formal "L-Ala-to-(S)-β-Aib mutations" can exert ferrocene helix inversion due to the different stereogenic carbon atoms of L -Ala and (S)-β-Aib. Furthermore, the mutation (de-)stabilizes the conserved secondary structure with two intramolecular hydrogen bonds, depending on the "mutation site". …
Complexes of organometallic compounds
1971
Abstract A number of novel compounds of dimethyllead(IV) and diphenyllead(IV) moieties with ligands having a rigid geometry when coordinating, have been prepared and characterized. The goal of the work was the building of model molecules for five-coordinated R 2 Pb IV , with known configuration of the CPbC skeleton. From spectroscopic data it is inferred that the complexes under investigation have a distorted bipyramidal trigonal structure, with the CPbC moiety allocated in the trigonal plane.
Complexes of organometallic compounds. XLVII. Synthesis of dimethyltin(IV) adenosinate and its characterization by Mössbauer and infrared spectroscopy
1977
Complexes of Organometallic Compounds. XXVII. Studies on Diorganolead (IV) Moieties Six-coordinated by ONNO Tetradentate Ligands
1972
New complexes R2PbL, where L2− are the dianions in the “planar” SCHIFF base form, of the tetradentate ONNO ligands α, α′ (ethylenedinitrilo)dicresol and 2,2′ bis-benzoxazoline, were synthesized. Their configuration was investigated at the solid state by infrared spectroscopy, and in solution phase mainly by electronic and PMR spectroscopy. An octahedral type structure with linear CPbC moieties, and the ONNO ligand atoms chelating PbIV in a square plane, was advanced. Darstellung neuer Komplexverbindungen: R2PbL (R = CH3, C2H5, C6H5; L−2 sind zweiwertige Anionen, in der „planaren” SCHIFFSCHEN Basen-Konfiguration, der vierzahnigen ONNO-Liganden Disalicylal-athylendiamin und Glyoxal-bis-[2-hyd…
Complexes of Organometallic Compounds. XXIV. Spectroscopic Studies on Complexes of Diorganotin(IV) Moieties with SNO and ONO Tridentate Ligands
1970
Komplexverbindungen vom Typ R2SnL (R = CH3, C6H5; L ist ein dreizahniger ONO- oder SNO-Ligand) werden dargestellt und ihre IR-, KMR- und elektronischen Spektren untersucht, um die Strukturen zu klaren. Als Liganden (LH2) werden benutzt: 4-(2-Benzothiazolinyl)-pentan-2-on, (hier zum ersten Mal dargestellt); 3-(o-Hydroxyphenylamino)crotonophenon; 2-(o-Hydroxyphenyl)-benzothiazolin; und N-o-Hydroxybenzyliden-o′-hydroxyanilin. Im festem Zustand umgeben die organischen Liganden L2− das Zinn(IV)-Atom als ebene dreizahnige Liganden. Die R2SnIV-Reste sind wahrscheinlich nicht linear. Eine mogliche Anordnung der Liganden ist eine trigonale Bipyramide, in der die zwei R-Reste und das Stickstoffatom i…
Complexes of organometallic compounds. LII. 119Sn Mössbauer isomer shifts, partial atomic charges on tin, and structure, in triorganotin(IV) halides
1988
Complexes of organometallic compounds. XLIX. A Mössbauer-zeeman spectroscopic study of glycylglycinato-O,N,N(2−) diphenyltin(IV), and the point-charg…
1978
Complexes of organometallic compounds. LI. The correlation between 119Sn Mössbauer isomer shifts and partial atomic charges on tin in R3SnL compounds
1985
Abstract The 119Sn Mossbauer isomer shift parameters, δ, of compounds R3SnL (R = AlK, Ph; L = F, Cl, OH, OR′, CN, NCS, NCO, N3) have been correlated to partial atomic charges on tin QSn, calculated according to a valence state electronegativity equalization procedure carried out by the CHELEQ program. A unique δ/QSn correlation has been obtained for all the five-coordinated R3SnL species by using average δ parameters for the AlK3IV derivatives.
Synthesis, characterization and a voltammetric study of (Bu4N)2[Mo2Br6]. Oxidation-reduction mechanism of related compounds
1984
The synthesis and characterization of (Bu4N)2[Mo2Br6], obtained from Mo(CO)6, (Bu4N)Br and 1,2-dibromoethane, is described. The electrochemical behaviour of [Mo2Br6]−2 and related species is studied, and an oxidation-reduction mechanism is proposed.