Synthesis of Novel Phenylazomethine Derivatives as a Multi-Dentate Ligand for Advanced Metal-Organic Hybride Nano-Materials

摘要

Oligophenylazomethines (OPAs) and the aniline-capped OPAs were synthesized via dehydration of 4-aminobenzophenone in the presence of TiCl_4 as a Lewis acid. TiCl_4 acts as an excellent dehydration agent for formation of the C=N bond. OPAs have some isomers, which are based on the E/Z conformation of the azomethine moieties. Novel cyclic molecules, the cyclic phenylazomethine trimer (CPA_3-ab) derivatives, were synthesized via the dehydration of the 4-aminobenzophenone. The yields of the macrocycles were enhanced to over 90% by induction of the bulky a-substituent to the substrate. The highly preferential formation of novel aabb-type phenylazo-methine macrocycles was also achieved. The resulting CPA_6-aabb has unique structure based on the E/Z conformation of the azomethine bonds, the extremely regular molecular-packing state. The novel dendritic phenylazomethines(DPAs), were synthesized by the convergent method. The DPAs have a high solubility unlike the conventional linear polyphenylazomethines. The tin chloride complexed to the imine groups of DPAs in a stepwise fashion. The complexation occurs in the order of 1st, 2nd, 3rd, and 4th layers of DPA G4.