Triple ions porphyrins

Interestingly, in the case of lanthanide ions as metal centers, triple decker porphyrin sandwich complexes were also synthesized and studied (Wittmer. Holten, 19%). 

The linking of j8-diketonates by bridges allows the formation of face-to-face complexes (11-XXVII) similar to those of face-to-face porphyrins (Section 9-12) small molecules may occupy the central hole. With trivalent ions such as Ti3+, V3+, Mn3+, or Fe3+, triple-helical structures consisting of two 6-coordinate M111 ions chelated by three bis(dike) ligands can be obtained.113... 

Selective complexation of di- and tetra-substituted porphyrins with cerium(III) ion led to novel double- and triple-decker sandwich complexes. In such complexes, the two or three porphyrin macrocyles were rotated by ca. 20-45. The various complexes were prepared by reaction of the parent porphyrins with cerium acetate. 

The dimer formation of anionic metalloporphyrins [677], cationic porphyrins [678], heterodimer formation [679-682], an aggregate between porphyrin and cytochrome c [683], and dimer formation through metal-metal interaction [684] has been reported. The 1 2 complex formation between the metal ions such as Th ° and Ce and porphyrins afforded an interesting double-decker sandwich complex [685-687] and a triple-decker one [688]. 

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