Fechem Abstract Band
Transcrição
Fechem Abstract Band
Investigation of Reactivity of some Novel 1,4,7-Triazacyclononane and 1,1,1-Tris(Aminomethyl)ethane Complexes in Catalysis of Alkene Epoxidation Željko Petrovskia, Marta Abrantesa, Isabel S. Gonçalvesb, Beatriz Royoa and Carlos C. Romãoa , aInstituto de Tecnologia Química e Biológica (ITQB) da Universidade Nova de Lisboa,Quinta do Marquês, apt 127, 2781-901 Oeiras, Portugal b Department of Chemistry, University of Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal e-mail: [email protected] Some VI group transition metal complexes of 1,4,7-triazacyclononane and 1,1,1tris(aminomethyl)ethane has been synthesised and tested as catalysts in alkene epoxidation with t-BuOOH. Some of these catalysts are presented (1-3). In recent years we have explored activity of N NH NH Mo variety of cis-L2MoX2O2 1 (L=N donors; X=Cl, Br, CH3) , organotin- Cl O Cl O 1 NH OC OC NH NH M N CO O 2 (M= Mo, Cr) BF4 N N Mo O Cl 3 oxometalates [(n-Bu3Sn)2MO4] (M= Mo, W)2, triphenylsiloxy complex MoO2(OSiPh3)23 and (η5-C5R5)MoO2Cl4 in catalytic olefin epoxidations with t-BuOOH. Following these studies we decided to explore the chemistry of group VI transition metal complexes in oxidation state 0 and VI of tridentate nitrogen complexes of 1,4,7-triazacyclononane (tacn) and 1,1,1tris(aminomethyl)ethane (tame) ligands. Preliminary results show that high selectivity and conversion up to 60 % was obtained in epoxidation of cyclooctene after 24 h at 55 ºC. The synthesis of catalyst and catalytic activity will be discussed. Acknowledgement: The authors thank to Fundação de Ciência e Tecnologia (FCT) for support of this work (project number Praxis XXI/BD /17264/99). 1 a) F.E. Kühn, A.D. Lopes, A.M. Santos, E. Herdtweck, J.J. Haider, C.C.Romão, A.G.J. Santos, Mol.Catal.A Chemical.,2000,151,147; b) F.E. Kühn, A.M. Santos, A.D. Lopes, I.S. Gonçalves, E. Herdtweck, C.C. Romão, J.Mol.Catal., 2000,164,25; c) P. Ferreira, I.S. Gonçalves, F.E. Kühn, A.D. Lopes, M.A. Martins, M. Pyllinger, A. Pina, J.Rocha, C.C. Romão, A.M. Santos, T.M. Santos, A.A. Valente, Eur.J.Inorg.Chem.2000,2263 2 M.Abrantes, A. Valente, M. Pillinger, I.S. Gonçalves, J. Rocha, C.C. Romão, J.Catalysis, 2002,209,237 3 M. Abrantes, A.A. Valente, M. Pillinger, I.S. Gonçalves, J. Rocha, C.C. Romão, Inorg.Chem.Commun., 2002,5,1069 4 M. Abrantes, A.M. Santos, J. Mink, F.E. Kühn, C.C.Romão, Organometallics, in press