A Kumada Coupling Catalyst, [Ni{(Ph2P)2N(CH2)3Si(OCH3)3-P,P }Cl2], Bearing a Ligand for Direct Immobilization Onto Siliceous Mesoporous Molecular Sieves

0444673 - ÚFCH JH 2016 RIV DE eng J - Článek v odborném periodiku
Stamatopoulos, I. - Giannitsios, D. - Psycharis, V. - Raptopoulou, C. P. - Balcar, Hynek - Zukal, Arnošt - Svoboda, J. - Kyritsis, P. - Vohlídal, J.
A Kumada Coupling Catalyst, [Ni{(Ph2P)2N(CH2)3Si(OCH3)3-P,P }Cl2], Bearing a Ligand for Direct Immobilization Onto Siliceous Mesoporous Molecular Sieves.
European Journal of Inorganic Chemistry. Roč. 2015, č. 18 (2015), s. 3038-3044. ISSN 1434-1948. E-ISSN 1099-0682
Grant CEP: GA ČR GAP108/12/1143
Institucionální podpora: RVO:61388955
Klíčová slova: homogenous catalysis * heterogeneous catalysis * cross coupling
Kód oboru RIV: CF - Fyzikální chemie a teoretická chemie
Impakt faktor: 2.686, rok: 2015

The ligand-exchange reaction between [Ni(PPh3)2Cl2] and (Ph2P)2N(CH2)3Si(OCH3)3 afforded the novel NiII complex [Ni{(Ph2P)2N(CH2)3Si(OCH3)3-P,P′}Cl2] (1) in which the square-planar NiP2Cl2 coordination sphere contains a four-membered Ni–P–N–P ring. Comparison of the structure of 1 and related NiII square-planar or Ni0 tetrahedral complexes containing similar P–N–P ligands shows that the magnitude of the P–Ni–P angle is controlled by the presence of the Ni–P–N–P ring, irrespective of the geometry of the nickel coordination sphere. Direct anchoring of 1 onto SBA-15 molecular sieves through the trimethoxysilyl end-group of the ligand afforded heterogeneous catalyst 1/SBA-15. Both 1 and 1/SBA-15 catalyze Kumada cross-coupling reactions, exhibiting similar activity and a slightly higher product selectivity than the [Ni{Ph2P(CH2)3PPh2-P,P′}Cl2] and [Ni{(Ph2P)2N-(S)-CHMePh-P,P′}X2] (X = Cl, Br) complexes described in the literature. The Grignard reagent employed is likely to induce leaching of the catalyst, which retains its activity in solution.
Trvalý link: http://hdl.handle.net/11104/0247210