Discotic liquid crystals of transition metal complexes. Part 32. Synthesis and liquid-crystalline properties of doubledeckers and tripledeckers based on cerium complexes of bis- and tetrakis(3,4-dialkoxyphenyl)porphyrin

摘要: Novel sandwich-type doubledecker and tripledecker cerium complexes, bis[5,15-bis(3,4-dialkoxyphenyl)porphyrinato]cerium(IV) (2: [(CnO)4BPP]2Ce; n = 14), bis[5,10,15,20-tetrakis(3,4-dialkoxyphenyl)porphyrinato]cerium(IV) (5: [(CnO)8TPP]2Ce; 8,10,12,14,16,18), tris[5,10,15,20-tetrakis(3,4-dialkoxyphenyl)porphyrinato]cerium(IV) (6: [(CnO)8TPP]3Ce2; 10), have been synthesized by using the corresponding metal free derivatives, 5,15-bis(3,4-dialkoxyphenyl)porphyrin (1: (CnO)4BPPH2) 5,10,15,20-tetrakis[3,4-bis(octadecyloxy)phenyl]porphyrins (4: (CnO)8TPPH2) which were previously reported to show a discotic lamellar(DL) mesophase. The mesophase structures of all these complexes characterized in detail microscopic observation, DSC measurements temperature-dependent X-ray diffraction studies. We investigated critical molecular structure changing from lamellar mesophase-showing porphyrins columnar ones. found that multideckers may exhibit mesophase, when central core is substituted more than twelve alkoxy chains.