Book Synopsis Synthesis, Chemistry, and Catalytic Activity of Complexes of Lanthanide and Actinide Metals in Unusual Oxidation States and Coordination Environments. Progress Report, February 1, 1977--January 31, 1978 by :
Download or read book Synthesis, Chemistry, and Catalytic Activity of Complexes of Lanthanide and Actinide Metals in Unusual Oxidation States and Coordination Environments. Progress Report, February 1, 1977--January 31, 1978 written by and published by . This book was released on 1977 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Research devoted to synthesis of new classes of lanthanide and actinide complexes is reported. Co-condensation of lanthanide metals with 1,3-butadiene (1,3-C4H6) or 2,3-dimethyl-1,3-butadiene (2,3-(CH3)2-1,3-C4H4) produces three types of organolanthanide complexes differentiated by their solubility in pentane, toluene and tetrahydrofuran (THF). The THF soluble species are formed in highest yield and have been most completely characterized. Elemental analysis shows that when butadiene is the ligand, complexes of empirical formula Ln(C4H6)3 (Ln = Nd, Sm, Er) are obtained. When dimethylbutadiene is used, Ln((CH3)2C4H4)2 is obtained (Ln = La, Nd, Sm, Er). These compounds differ from all other organolanthanide complexes in several respects. First, it is unusual to be able to obtain such good analytical data. Generally, for organolanthanides, incomplete carbon and hydrogen combustion is observed. Second, the stoichiometries are difficult to reconcile with known lanthanide chemistry. If the dienes coordinate as .pi.-ligands, the metals are formally zero-valent. If the dienes coordinate as dialkyl-2-butene moieties, the metals must be in the +6 oxidation state in the butadiene series and the +4 oxidation state in the dimethylbutadiene series. The physical properties of these new complexes are also unusual. The sharp, line-like, 4f-4f optical transitions normally observed for lanthanide complexes are not observed in the visible and near infrared regions. Instead a single broad band dominates the spectrum. The room temperature magnetic moments are similarly not consistent with known Ln/sup 3 +/ species. Most unusual in this respect is the lanthanum complex, which is the first paramagnetic organolanthanum complex ever observed. Further investigations of diene reactions with lanthanides in chemical reduction syntheses are summarized. (JRD).