Résumé
Tetracyanoethylene (TCNE) is a very important starting compound in modern synthetic and materials chemistry. The great variety of its numerous reaction modes and chemical versatility have been surveyed in a very recent fundamental review by Miller. It was particularly emphasized that a wide array of products based on TCNE is available and that the understanding of their structures and properties is very challenging. Here, we report a new macrocyclic structure designed from TCNE molecules as the structural unit by a template synthesis involving vanadyl or Yb3+ ions. We have found that the interaction of TCNE with bis-(arene)vanadium in acetonitrile, extensively described previously, can have an unexpected sequel when the reaction mixture is allowed to contact air and moisture. Within an hour the black suspension formed under vacuum by interaction of bis(benzene)vanadium and TCNE in acetonitrile at room temperature is converted to a deep green solution. The product of the reaction was purified from excess TCNE and arene ligand by washing with benzene which binds free TCNE by formation of a charge transfer complex. After careful removal of benzene by heating the product under vacuum a dark green solid soluble in THF, acetonitrile, DMF and DMSO was obtained in 50-60% yield. The ESR spectrum of an acetonitrile solution showed an anisotropic signal with g = 1.960, a = 175 and g> =