Porphyrinogen expanded

Acid-induced cyclization of the appropriate (hydroxypropenyl)pyrroles 30, which can be easily derived from a-unsubstituted pyrroles by vinylogous Vilsmeier reaction followed by reduction of the formyl function, yields the corresponding expanded porphyrinogens 31. The... 

An acid catalyzed double Schiff-base condensation of 5 with o-phenylenediamine, 6, then gives the cyclic non-aromatic sp3 texaphyrin ring 7, a macrocyclic product that can be viewed as being an expanded porphyrinogen [24], The sp3 form can be oxidized with ferrocenium ion to give the corresponding aromatic derivative, namely the metal-free sp2 form 8 (Scheme 2) [25],... 

The synthesis of a tripyrrane containing porphyrinogen-like macrocycle was reported by Sessler et al. in 1987 [59]. As discussed in the previous section (4.3), the first representative of this new class of expanded porphyrins (e.g. 115) was formed by the Schiff base condensation between a diformyltripyrrane 114 and... 

As implied above, the success enjoyed with the texaphyrins has inspired the synthesis of several other [1 + 1] Schiff base systems (e.g., 9.92, 9.93, and 9.95 Schemes 9.1.14 and 9.1.15). One of these, an anthracene-derived expanded porphyrinogen (structure 9.95 Scheme 9.1.15) is considered particularly noteworthy. ... 

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