SOLID-STATE POLYMERIZATION REACTIONS OF METAL SALTS AND COMPLEXES: CRYSTAL ENGINEERING, STRUCTURE AND REACTIVITY

Many different types of reactions can occur in the solid state. This thesis discusses the solid-state polymerization of metal salts and complexes. Unsaturated counterions are bonded to alkali or alkaline earth metal ions. Unsaturated ligands are coordinated to transition-metal ions. The unsaturated moieties undergo vinyl or acetylenic addition reactions in the crystal lattice. Amorphous polymers are produced from crystalline monomers during irradiation.;The solid-state reactivities of propiolate salts and complexes were reported as early as 1965 by Davidov and co-workers. However, the structural properties of these compounds were never subsequently investigated. This thesis elucidates for the first time the packing arrangements of these materials in the crystal lattice and suggests possible pathways along which the polymerization reaction can occur. The reaction rate, mechanism and manner in which crystalline monomer is transformed to amorphous polymer is thoroughly investigated and discussed. Finally, the molecular structures of the amorphous polymeric products are characterized by spectroscopic analytical methods.;The new crystal engineering strategy of "structure-mimicry" is introduced in this text. This strategy proposes that transition-metal complexes bearing unsaturated ligands can be forced to imitate, during crystallization, the packing arrangements of model complexes bearing saturated ligands whose crystal structures were studied and pre-determined as "favorable," i.e., satisfying the structural requirements of the topochemical postulate. The application of this strategy resulted in the discovery of many new unsaturated transition-metal complexes which could be synthesized, crystallized and successfully polymerized in the solid-state. The ligand molecule, (beta)-acryloxypropionate, was especially versatile in its ability to assume reactive packing arrangements when bonded to and crystallized with different metal ions.