293731-94-9Relevant academic research and scientific papers
Cyclooligomerization reactions of different phosphaalkynes in the presence of [W(CO)5thf] - A route to tungsten-stabilised phosphorus heterocycles
Kramkowski, Peter,Scheer, Manfred
, p. 1869 - 1876 (2007/10/03)
The reactivity of various phosphaalkynes versus [W(CO)5thf] has been studied. The reaction with Mes*C≡P (Mes* = 2,4,6-tBu3C6H2) exclusively leads to the low yield formation of [W(CO)2{(η2-PCMes*)W(CO)5}2] (1). The reaction of the less bulky tBuC≡P with [W(CO)5thf] results in high yields in [W(CO)2{η4-(tBuC)2P2W(CO)5}{η2-(tBuCP)W(CO)5}] (2) which possesses a 1,3-diphosphete ligand as well as a side-on coordinated tBuCP unit. Experiments employing MesC≡P (Mes = 2,4,6-Me3C6H2) give the complexes [W(CO)4{η4-(MesC)2P2}] (3), [W(CO)2{η4- (MesC)2P2}{η2-(MesCP)W-(CO)5}] (4) and [W(CO)2{η4- (MesC)2P2W(CO)5}2-(MesCP)W(CO)5{μ-W(CO)4}>] (5) which have a 1,3-diphosphete ligand in their coordination sphere and are partly substituted with an additional side-on coordinated MesC≡P unit. In 5, two P atoms of the 1,3-diphosphete and the side-on coordinated MesC≡P are further bridged by a W(CO)4 moiety. Additionally, the unusual product [{W(CO)3}6-1,2,4-(RC)3P3{RCP→W(CO)5}2>] (R = Mes) (6) resulting from a pentamerization of MesC≡P initiated by [W(CO)5thf], could be obtained in moderate yield. Comprehensive spectroscopical and structural investigations of all products are presented.
