Oligothiophene dendrimers

In a separate study, we have reported the use of aliphatic ether dendrimers as a solubilizing platform for the preparation of soluble oligothiophenes with minimal main-chain substitution (Figure 7.16B) [67], Aliphatic ether dendritic blocks... 

Figure 7.16 (A) Dendron-capped poly(triacetylene) and, (B) soluble oligothiophenes obtained by dendrimers assisted synthesis...

Some dendrimers (389-391) have been reported. The thiophene-containing dendrimers are promising materials, due to the unique properties of oligothiophenes and their derivatives, such as high charge carrier mobility, efficient fluorescence, excellent stability in ambient conditions (even at elevated temperatures), and easy functionalization. 

As with chromophores, the steric encapsulation of a dendrimer core can be utilized to prevent intermolecular interactions between redox active sites. A number of different redox active core moieties have been investigated, including, iron—sulfide clusters,9394 bis(terpyridine)iron(II) complexes,92 tris-(bipyridine)ruthenium(II) complexes,330 zinc porphyrins,252 oligothienylenevinylenes,331 fullerenes,236,332 ferrocenes,333-336 oligothiophenes,322 oligonaphtha-lenes,337 and 4,4 -bipyridinium.338... 

The peripheral functionalization of conventional dendrimers containing flexible and saturated spacers with oligothiophenes was reported by Miller et al. [498], Bi- and quaterthiophenes were attached to the periphery of the 36-acid terminated G2-dendrimer through esterification with a (2-hydroxyethyl)thio linker (Chart 1.74). The moderate conductivity of l2-doped films of dendrimers 5.52 and 5.53 increased by two orders of magnitude when they were exposed to solvent vapors. 

In Section 1.5, recent approaches to 3D star-shaped and dendritic structures are described. Linear oligothiophenes decorated with classical dendrons or dendrimers which are substituted by smaller oligothiophenes appeared on the scene. Then, in the last few years, aZZ-thiophene dendritic structures came up as highly... 

A. Petrella, J. Cremer, L. De Cola, P. Bauerle and R. M. WiUiams, Charge transfer processes in conjugated triarylamine-oligothiophene-perylenemonoimide dendrimers, J. Phys. Chem. A, 109, 11687-11695 (2005). 

P. R. L. Malenfant, L. Groenendaal and J. M. J. Fr6chet, Well-defined triblock hybrid dendrimers based on lengthy oligothiophene cores and poly(benzyl ether) dendrons, J. Am. Chem. Soc., 120, 10990-10991 (1998). 

Adronov A, Malenfant PRL, Frechet JMJ (2000) Synthesis and steady-state photophysical properties of dye-labeled dendrimers having novel oligothiophene cores a comparative study. Chem Mater 12 1463-1472... 

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