213404-26-3Relevant academic research and scientific papers
Spectroscopic properties, structure and reactivity of [WCl(SnCl3)(CO)3(NCMe)2]
Szymanska-Buzar, Teresa,Glowiak, Tadeusz
, p. 3419 - 3426 (2008/10/09)
A series of seven-coordinate tungsten(II) nitrile complexes of the type [WCl(SnCl3)(CO)3(NCR)2](1-4), R=Me, Et, n-Bu, Ph, has been synthesized. These new complexes have been characterized by IR, NMR and UV-vis spectroscopy. In addition single-crystal X-ray diffraction was used to structurally characterize [WCl(SnCl3)(CO)3(NCMe)2](1). The most prominent feature of complex 1 is the facility by which acetonitrile and carbonyl ligands can be replaced by other ligands. Complexes were isolated in which CO and acetonitrile ligands were substituted by alkyne ligands. The alkyne tungsten(II) complexes 5-8 formed were structurally characterized by IR and NMR spectroscopy. The complex 1 has been found to be an active catalyst for the polymerization of phenylacetylene. The structures and mechanisms of the formation of various new types of complexes and their role in the catalytic process are discussed.
Synthesis, structure and reactivity of novel W-Ge chlorocarbonyl compounds. X-raycrystal structure of [WCl(GeCl3)(CO)3(NCEt)2]
Szymanska-Buzar, Teresa,GlLowiak, Tadeusz
, p. 143 - 153 (2007/10/03)
The reaction of GeCl4 with tungsten(0) compounds yielded heterobimetallic W-Ge complexes. The novel dinuclear complex [(CO)4W(μ-Cl)3W(GeCl3)(CO)3] 1 was obtained together with [W(CO)5(GeCl2)] 2 in a photochemical reaction of W(CO)6 with GeCl4. The mononuclear seven-coordinate complex [WCl(GeCl3)(CO)3(NCMe)2] 3 was formed in a reaction of complex 1 with acetonitrile or in a reaction of [W(CO)4(NCMe)2] with GeCl4 in dichloromethane. A single-crystal X-ray diffraction study of the complex [WCl(GeCl3)(CO)3(NCEt)2] 4 showed that the environment of the tungsten atom is a distorted capped octahedron with the GeCl3 anionic ligand occupying the unique capping position above an octahedral face defined by the three carbonyl groups. The position of the GeCl3 ligand is approximately trans to the W-Cl bond. The dinuclear complex 1 and the mononuclear complex 3 show similar behavior in reaction with alkynes. Complexes were isolated in which CO or/and acetonitrile ligands were replaced by alkyne ligands. The alkyne tungsten(II) complexes 7-13 formed were structurally characterized by IR and NMR spectroscopy. However, the reaction of 1 and 3 with phenylacetylene (PA) leads to polymerization and formation of a high molecular weight polyphenylacetylene (PPA). The structures and mechanisms of the formation of various new types of complexes and their role in the catalytic process are discussed.
