Polymer-supported complexes. Part 2. Polystyrene-anchored pentane- 2,4-dionato-complexes of transition metals: synthesis, reactions, and catalytic properties

Abstract

Soluble and divinylbenzene cross-linked (8%) polystyrene functionalized with 'pd' groups (Hpd = pentane-2,4-dione) interact with M(pd)_n(M = Fe, n= 3; M = Co, n= 2; M = Cu. n= 2; M = Zr, n= 4), [VO(pd)₂], [Rh(CO)₂(pd)], TiCl₄, [Ni(en)₂]Cl₂(en = H₂NCH₂CH₂NH₂), and FeCl₃ to give polymer-anchored metal complexes. Thermal decarbonylation of polymer-anchored [Rh(CO)₂(pd)], monitored by i.r. spectroscopy, suggests formation of a partially decarbonylated pd-bridged intermediate followed by Rh-pd bond cleavage. Hydrogenation of cyclohexene at 109 °C and atmospheric pressure of cyclohexene is catalysed by polymer-supported [Fe(pd)₃] and [Rh(CO)₂(pd)]. Formation of metal crystallites on the polymer seems to be responsible for the observed catalytic activities.