Construction of Regulated Nanospace around a Porphyrin Core

Abstract

A series of 1,3,5-phenylene-based rigid dendritic porphyrins were synthesized by Suzuki coupling between a porphyrin core and dendron units. The intramolecular energy transfer was studied by absorption and fluorescence spectroscopies. The encapsulation of the porphyrin core within the 1,3,5-phenylene dendron units was found to provide highly efficient energy transfer from the dendron units to the porphyrin core. The dendritic wedge structure affected the energy transfer efficiency. The 1,3,5-phenylene-based rigid dendron units act as highly efficient light-harvesting antennae. These dendritic porphyrins have also been examined as C(60) hosts and substrate-selective oxidation catalysts. The attachment of the second generation of 1,3,5-phenylene-based dendron units with the porphyrin core enabled a stable inclusion of C(60) in toluene. Furthermore, the size and shape of the nanospace in the rigid dendritic porphyrins were found to affect the selectivity of substrates in the catalytic olefin oxidations.

Fullerene‐Containing Liquid Crystals

“…In this respect, Kimura et al [68] have synthesized 1,3,5-phenylene-based rigid dendritic porphyrins with well-defined nanospaces formed around the porphyrin core that provide cavities for inclusion of C 60 . In addition, the dendritic porphyrin moiety interacts strongly with C 60 through π-donor/π-acceptor interactions, leading to a very good stability of the complex in toluene.…”

Polyester Dendrimers

“…Porphyrins were selected as core molecules because of their potential applications in many areas [156][157][158][159]. Reports dealing with porphyrins decorated with dendrimers had previously appeared [112,[160][161][162][163][164][165][166][167][168]. After investigating three different synthetic strategies for this study, it was concluded that a spacer was required to be attached to the porphyrin to increase the hydrolytic stability and allow synthesis of higher generations.…”

Synthesis and Photophysical Properties of Pyrene-Based Multiply Conjugated Shaped Light-Emitting Architectures: Toward Efficient Organic-Light-Emitting Diodes

“…Thus, pyrene is a fascinating core for constructing fluorescent-conjugated light emitting dendrimers. In addition, several types of chromophoric dendrimers backbone such as polyphenylene (Gong et al, 2001;Xu et al, 2002;Kimura et al, 2001), poly(phenylacetylene) (Xu  Moore, 1993;Meliger et al, 2002), and poly(benzyl ether) (Jiang  Aida, 1997;Harth et al, 2002) have been widely used as light absorbers, and the energy was efficiently funnelled to the core accepter. In this section, we presented the synthesis and photophysical properties of pyrene-cored light-emitting dendrimers that have been investigated for the preparation of optoelectronically active solution-processable light emitting dendritic materials and concentrate on the potential applications in OLEDs, in www.intechopen.com www.intechopen.com which some light emitting dendrimers have been used.…”