Cristina G. de Azevedo

Publications (3)5.88 Total impact

• Article: (Pentabenzylcyclopentadienyl)molybdenum Complexes: Synthesis, Structures and Redox Properties

  Sónia Namorado, Jinlan Cui, Cristina G. de Azevedo, M. Amélia Lemos, M. Teresa Duarte, José R. Ascenso, Alberto R. Dias, Ana M. Martins
  Berichte der deutschen chemischen Gesellschaft 02/2007; 2007(8):1103 - 1113. · 2.94 Impact Factor
• Article: Titanium Triamidotriamine Compounds: Syntheses, Structures and Redox Properties

  Ana M. Martins, José R. Ascenso, Cristina G. de Azevedo, Alberto R. Dias, M. Teresa Duarte, Humberto Ferreira, M. João Ferreira, Rui T. Henriques, M. Amélia Lemos, Li Li, João F. da Silva
  Berichte der deutschen chemischen Gesellschaft 04/2005; 2005(9):1689 - 1697. · 2.94 Impact Factor
• Article: Insertion of Isocyanides into Group 4 Metal−Carbon and Metal−Nitrogen Bonds. Syntheses and DFT Calculations

  Ana M. Martins, José R. Ascenso, Cristina G. de Azevedo, Alberto R. Dias, M. Teresa Duarte, João F. da Silva, Luís F. Veiros, Sandra S. Rodrigues
  [show abstract] [hide abstract]
  ABSTRACT: The reactions of [Ti(η5-Ind)(NMe2)2Me], [Ti(η5-Ind)(NMe2)Cl2], and [Zr(η5-Ind)(NMe2)2Cl] with 2,6-dimethylphenyl isocyanide (CN(2,6-Me2Ph)) and tert-butyl isocyanide (CN-t-Bu) have been investigated. For the first complex, insertion occurs exclusively into the Ti−C bond to give [Ti(η5-Ind)(NMe2)2{C(Me)N-t-Bu}] (1), which, according to DFT results, is due to the weakness of the Ti−CH3 bond when compared to Ti−NR2. [Ti(η5-Ind)(NMe2)Cl2] was found to react with 1 equiv of CN(2,6-Me2Ph) to yield [Ti(η5-Ind){C(NMe2)N(2,6-Me2Ph)}Cl2] (2). Two equivalents of 2,6-dimethylphenyl isocyanide reacts with [Zr(η5-Ind)(NMe2)2Cl] to give the double insertion compound [Zr(η5-Ind){C(NMe2)N(2,6-Me2Ph)}2Cl] (3). The same reaction performed with CN-t-Bu proceeds slowly and enabled the characterization, by NMR, of [Zr(η5-Ind)(NMe2){C(NMe2)N-t-Bu}Cl] (4) and [Zr(η5-Ind){C(NMe2)N-t-Bu}2Cl] (5). The molecular structures of 2 and 3 have been determined by X-ray diffraction. DFT calculations of the insertion of CNH in the zirconium nitrogen bonds of [Zr(η5-Ind)(NR2)2Cl] (R = H, Me) have been performed and show that the progressive stability of the insertion products accounts for the experimentally found double insertion product.
  09/2003;