A facile route for the electrochemical generation of an olefin metathesis catalyst from methylene chloride solution of WCl6 was described. It was found that reductive, oxidative and pulse electrolysis produced the same intermediate. This electrolysis intermediate incorporates olefin into its structure possibly forming a metal-olefin complex, which decomposes into catalytically active metal carbene type species. ESCA, NMR and ESR methods were used to elucidate the structure of the catalyst system. The catalyst was applied in the metathesis of 1-octene and 2-octene without any need for a co-catalyst. Highly specific products with high yields were obtained. © 2003 Elsevier B.V. All rights reserved

A typical low-strain monomer, cyclooctene, was polymerized via ring-opening metathesis polymerization with electrochemically produced active species. The structural properties of the polyoctenamer were determined by NMR, gel-permeation chromatography and differential scanning calorimetry. Analysis of the polyoctenamer microstructure by 1 H and 13 C NMR spectroscopy indicates that the polymer contains a highly cis stereoconfiguration of the double bonds (σ c = 0.75). The resulting polymer is of low molecular weight and has a reasonably broad molecular weight distribution (M w = 18 000, PDI = 1.9). The glass transition temperature and melting point of the polyoctenamer are −11.3 • C and 36.5 • C respectively.

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The ring-opening metathesis polymerization of cyclododecene using an electrochemically reduced tungsten-based catalyst (WCl 6 -e − -Al-CH 2 Cl 2 ) is described. In addition, the influence of reaction conditions on the polymerization yield was determined. The resulting polymer has been characterized by NMR, IR, gel permeation chromatography and differential scanning calorimetry. The glass transition temperature and melting point of the polydodecenamer are 19.6 • C and 70.0 • C respectively. Furthermore, cyclododecene has been polymerized into a low-molecular-weight polymer (12.0 × 10 3 ) with a polydispersity of 2.06 in high yields (94%). IR and NMR analysis indicate that the polydodecenamer has a high trans content (60%).

Electrochemically generated tungsten-based active Electrochemically generated tungsten-based active species as catalysts for metathesis-related reactions: 1. species as catalysts for metathesis-related reactions: 1. Acyclic diene metathesis polymerization of 1,9-decadiene Acyclic diene metathesis polymerization of 1,9-decadiene Okan Dereli, Bu È lent Du È z, Birgu È l Zu È mreog AE lu-Karan* and Yavuz I Ç mamog AE lu* Hacettepe University, Chemistry Department, 06532 Ankara, Turkey The application of the WCl 6 ±e À ±Al±CH 2 Cl 2 system to acyclic diene metathesis polymerization of 1,9-decadiene is reported. The polyoctenamer formed is of a weight-average molecular weight of 9000 with a polydispersity of 1.92. IR and NMR spectral analyses indicate the retention of the double bonds in the polymer structure with high trans content as expected from a step condensation reaction. This relatively stable catalytic system, however, also activates the competing vinyl addition reactions while being inactive in ring-closure metathesis reactions.