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Chlorido Ligand (chlorido + ligand)
Selected AbstractsAiding Factors in the Formation of Azaplatinacyclobutane Rings , X-ray and Crystal Structure of [Pt{CH(Ph)CH2NEt2 -,C,,N}(N,N,N,,N, -tetramethylethylenediamine)]+ and of Its Open-Chain PrecursorEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 15 2007Giuseppe Lorusso Abstract The addition products 2 of a secondary amine to a coordinated olefin, in the cationic complexes [PtCl(,2 -CH2=CHR)(tmeda)]+ (tmeda = N,N,N,,N, -tetramethylethylenediamine; R = Me, 1a; Ph, 1b, H, 1c), undergo in basic medium an intramolecular nucleophilic substitution with elimination of the chlorido ligand and formation of an azaplatinacyclobutane ring 3. The ring-closing process occurs notwithstanding the absence of a labilizing ligand trans to the leaving chlorido ligand and of bulky substituents on the amino,ethanide chain. If the addition product 2 is a mixture of Markovnikov and anti-Markovnikov isomers, the ring-closing reaction is faster for the anti-Markovnikov form, and this leads to an increase of the relative amount of the anti-Markovnikov isomer in the cyclized species 3. The difference in the rate of formation of the azaplatinacyclobutane ring between the two isomers has been interpreted on the basis of a more favorable stereochemistry in the case of the anti-Markovnikov form. The X-ray crystal structures of [Pt{CH(Ph)CH2NEt2 -,C,,N}(tmeda)]+ (3bn) and of its open-chain precursor, [PtCl{CH(Ph)CH2NHEt2}(tmeda)]+ (2bn) fully support this hypothesis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Mapping the Transformation [{RuII(CO)3Cl2}2],[RuI2(CO)4]2+: Implications in Binuclear Water,Gas Shift ChemistryCHEMISTRY - A EUROPEAN JOURNAL, Issue 8 2010Moumita Majumdar Abstract The complete sequence of reactions in the base-promoted reduction of [{RuII(CO)3Cl2}2] to [RuI2(CO)4]2+ has been unraveled. Several ,-OH, ,:,2 -CO2H-bridged diruthenium(II) complexes have been synthesized; they are the direct results of the nucleophilic activation of metal-coordinated carbonyls by hydroxides. The isolated compounds are [Ru2(CO)4(,:,2 - C,O -CO2H)2(,-OH)(NPF -Am)2][PF6] (1; NPF -Am=2-amino-5,7-trifluoromethyl-1,8-naphthyridine) and [Ru2(CO)4(,:,2 - C,O -CO2H)(,-OH)(NP-Me2)2][BF4]2 (2), secured by the applications of naphthyridine derivatives. In the absence of any capping ligand, a tetranuclear complex [Ru4(CO)8(H2O)2(,3 -OH)2(,:,2 - C,O -CO2H)4][CF3SO3]2 (3) is isolated. The bridging hydroxido ligand in 1 is readily replaced by a ,-donor chlorido ligand, which results in [Ru2(CO)4(,:,2 - C,O -CO2H)2(,-Cl)(NP-PhOMe)2][BF4] (4). The production of [Ru2(CO)4]2+ has been attributed to the thermally induced decarboxylation of a bis(hydroxycarbonyl),diruthenium(II) complex to a dihydrido,diruthenium(II) species, followed by dinuclear reductive elimination of molecular hydrogen with the concomitant formation of the RuIRuI single bond. This work was originally instituted to find a reliable synthetic protocol for the [Ru2(CO)4(CH3CN)6]2+ precursor. It is herein prescribed that at least four equivalents of base, complete removal of chlorido ligands by TlI salts, and heating at reflux in acetonitrile for a period of four hours are the conditions for the optimal conversion. Premature quenching of the reaction resulted in the isolation of a trinuclear RuI2RuII complex [{Ru(NP-Am)2(CO)}{Ru2(NP-Am)2(CO)2(,-CO)2}(,3:,3 - C,O,O, -CO2)][BF4]2 (6). These unprecedented diruthenium compounds are the dinuclear congeners of the water,gas shift (WGS) intermediates. The possibility of a dinuclear pathway eliminates the inherent contradiction of pH demands in the WGS catalytic cycle in an alkaline medium. A cooperative binuclear elimination could be a viable route for hydrogen production in WGS chemistry. [source] | ||||||||||