Homobinuclear copper(I) hexafluoroacetylacetonate complexes with non-cyclic diene ligands

摘要

Binuclear copper(I) hexafluoroacetylacetonate (hfac) complexes with non-cyclic divinyl ligands of [Cu-I(hfac)](2)L composition (1) L = 1,5-hexadiene (HD), (2) L = allyl ether, (3) L = diallyldimethylsilane, (4) L = 1,3-divinyltetramethyldisiloxane were prepared. Sublimation tests showed that the complexes 1 and 4 are most thermally stable and can be sublimated at 50-70 degreesC in a vacuum (5 x 10(-4) Torr) with good yield (>80%). The new yellow crystalline complex 4 is air stable at room temperature and 1 is stable under an inert atmosphere. These complexes were characterized by NMR spectroscopy, TG-DSC analysis and single crystal X-ray diffraction. The [Cu(hfac)](2)L composition for both complexes is realized by copper atom coordination to one vinyl and one hexafluoroacetylacetonate group. The main reason of volatility and thermal stability of compounds 1 and 4 is high symmetry and hence low polarity of their molecules resulting in a relatively low energy of the lattice. Higher thermal stability of 4 in comparison with I is due to the stronger metal-ligand bonding due to the presence of dimethylsilyl groups. (C) 2003 Elsevier Ltd. All rights reserved.