Linear porphyrin oligomers

Figure 1-11 Effective molarities and binding constants for cyclization of linear porphyrin oligomers, by Glaser coupling in dichloromethane.

Anderson, S., H.L. Anderson, and J.K.M. Sanders (1995). Template-directed synthesis of linear and cyclic butadiyne-linked porphyrin oligomers up to a linear octamer. J. Chem. Soc. Perkin Trans. 1 2247—2254. 

Linearly expanded porphyrin oligomers and polymers with enhanced third-order susceptibilities have also been reported. In solution the conjugation lengths of single-strand chains can be strongly limited by rotation and disorder. The self-assembly of double-strand ladder complexes of porphyrin butadiyne oligomers 21 achieves amplification in the nonlinearity... 

In 2005, Rowan, Nolte, and coworkers described an efficient and templated synthesis of porphyrin boxes using DCC and reversible metathesis reaction [54]. Cyclic tetramers were successfully prepared in good yields (62%) from an olefin-functionalized zinc porphyrin in the presence of first generation Grubb s catalyst and upon addition of a tetrapyridyl porphyrin (TPyP) serving as a template. While a mixture of linear and cyclic oligomers was obtained in the absence of template, addition of TPyP resulted in a reorganization of the DCL to favor the formation of the desired tetrameric box (Fig. 7a). 

Soon after Guldi et al. published on their system, Stod-dart and coworkers published a report wherein dynamic chemistry was used to form self-assembled oligomers that were found to be capable of binding and, possibly even, sorting SWNTs by size. Their system is composed of 5,15-fran.y-pyridyl metalloporphyrin, 13, which can act as a linear divalent ligand and cw-protected Pd or Pt complexes (Figure 13). While neither the Pd/Pt ligand nor the porphyrin displayed an ability to solubilize SWNTs on its own, they were found to completely solubilize SWNTs in aqueous acetonitrile solutions when used in conjunction with one another. 

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