Formation of novel ene-yne substituted β-diketonato ruthenium(III) complexes by the Heck-like reactions on coordinated ligand
摘要:
Two new ene-yne substituted 2,4-pentanedionatoruthenium(III) complexes formed by the Heck-like reactions in the course of the Sonogashira reactions. The two complexes are structural isomers; one is [Ru(E-1,4-mBSima)(dpm)(2)] and another is [Ru(E-2,4-mBSima)(dpm)(2)], where E-1,4-mBSima is E-3-(1,4-bis(trimethylsilyl)-1-butene-3-ynyl)-2,4-pentanedionate, E-2,4-mBSima is E-3-(2,4-bis(trimethylsilyl)-1-butene-3-ynyl)-2,4-pentanedionate, and dpm is dipivaloylmethanate (2,2,6,6-tetramethylheptan-3,5-dionate). Both of complexes have been characterized by (1)H NMR and infrared spectroscopies, mass spectrometry, and electrochemistry. [Ru(E-1,4-mBSima)(dpm)(2)] has also been characterized by X-ray crystallography. The ruthenium(III) is coordinated in an octahedral arrangement by the oxygen atoms of three beta-diketonate ligands. The dihedral angle between the 2,4-pentanedionato chelate ring and the ene-yne plane on the E-1,4-mBSima ligand is 91 degrees. The ene-yne group in [Ru(E-1,4-mBSima)(dpm)(2)] is fixed either in the solution state suggested by the (1)H NMR spectrum with no symmetry. (C) 2011 Elsevier B.V. All rights reserved.