PAMAM-type Dendron

Bissett, M.A., et al., Dye functionalisation of PAMAM-type dendrons grown from vertically aligned single-walled carbon nanotube arrays for tight harvesting antennae. Journal of Materials Chemistry, 2011. 21(46) p. 18597-18604. 

Alper et al.97,98 immobilized palladium-modified PAMAM-like dendron complexes onto silica for carbonylation of iodobenzene in MeOH to generate methyl benzoate under low pressures of CO at 100°C. Product yields were high overall and the catalyst could be recycled 4 5 times without significant loss of activity. This type of PAMAM-type dendron-Pd complex was also used for the oxidation of terminal alkenes to generate methyl ketones under mild conditions 99 oxidative selectivity toward the terminal versus internal double bonds was also determined. 

Huang, B., and Tomalia, D.A. (2005) Dendronization of gold and CdSe/cdS (core-shell) quantum dots with tomalia type, thiol core, functionalized poly(amidoamine) (PAMAM) dendrons. J. Lumin. Ill, 215-223. 

Dendrons and dendrimers are the most intensely investigated subset of dendritic polymers. In the past decade, over 6,000 literature references have appeared dealing with this xmique class of structure-controlled polymers. The word dendrimer is derived from the Greek words dendri- (tree branch-like) and meros (part of), and was coined by Tomalia et al. about 20 years ago in the first full paper on poly (amidoamine) (PAMAM) dendrimers [47,72]. Since this early disclosure, over 100 dendrimer compositions (families) and 1,000 dendrimer surface modifications have been reported. The two most widely studied dendrimer families are the Frechet-type polyether compositions and the Tomalia-type PAMAM dendrimers. PAMAM dendil-mers constitute the first dendrimer family to be commercialized, and represent the most extensively characterized and best-understood series at this time [46]. 

Parallel studies on Tomalia type PAMAM dendrimers, the Frechet type poly(ether)dendrons, and other dendrimer families have generated an extensive list of unique properties driven by the dendritic state. Figure 42.14 compares several significant physical property differences between the linear and dendritic topologies related to conformations, crystallinity, solubilities, intrinsic viscosities, entanglement, diffusion/mobility, and electronic conductivity. 

Additional examples of dendritic-type surfactants were reported in the early patent literature as hydrophobic core functionalized PAMAM dendrons [35,168]. For example, when the core was a 12 carbon chain, the first two generation PAMAM dendrons exhibited hydrocarbon solubility (TMF). 

More recently, non-traditional polymerization strategies have evolved to produce a fourth new major polymer architecmral class, now referred to as dendritic polymers [43]. This new architectural polymer class consists of four major subsets (1) random hyperbranched, (2) dendrigrafts, (3) dendrons and (4) dendrimers. Dendrimers, the most extensively studied subset were discovered by the Tomalia group while in The Dow Chemical Company laboratories (1979) and represent the first example of synthetic, macromolecular dendritic architecture [43,44]. First use of the term dendrimer appeared in preprints for the first SPSJ International Polymer Conference, held in Kyoto, Japan in 1984 [45]. The following year, a full article in Polymer Journal [46] (Fig. 8) described the first preparation of a complete family of Tomalia-type poly(amidoamine) (PAMAM) dendrimers (G = 1-7) and their use as precise, fundamental building blocks to form poly (dendrimers) or so-called starburst polymers. These poly(dendrimers) are now referred to as megamers [47, 48] and are described in more detail later in Sect. 6.4.3. Other pioneers in the dendritic polymer field include Vogtle, Newkome, Frechet, Majoral, and others. These historical contributions have been reviewed recently [52]. ... 

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