Decorating diruthenium compounds with Fréchet dendrons via the click reaction

A series of dendronized-Ru(2) compounds were prepared using the Cu(I)-catalyzed 1,3-dipolar cycloaddition (click reaction) between the terminal azides of azidopoly(benzyl ether) dendrons ([D(n)]-N(3), n = 0-3) and Ru(2) units bearing one or two terminal ethynes, Ru(2)(D(3,5-Cl(2)Ph)F)(4-m)(DMBA-4-C(2)H)(m)Cl with m = 1 and 2, and D(3,5-Cl(2)Ph)F and DMBA-4-C(2)H as N,N'-bis(3,5-dichloro-phenyl)formamidinate and N,N'-dimethyl-4-ethynylbenzamidinate, respectively. The resultant Ru(2)(D(3,5-Cl(2)Ph)F)(4-m)(DMBA-D(n))(m)Cl compounds were further functionalized by the axial ligand displacement of Cl by -C(2)Ph to yield new compounds Ru(2)(D(3,5-Cl(2)Ph)F)(4-m)(DMBA-D(n))(m)(C(2)Ph)(2) (where m = 1 and 2; n = 0 and 1). All Ru(2) compounds reported herein were analyzed via mass spectrometry, voltammetry, and UV-visible and fluorescence spectroscopy. Density-functional theory (DFT) calculations were performed on a model compound to gain more insight into the molecular orbital energy levels possibly associated with the photophysical data obtained and presented herein.     

Synthesis and characterization of dendronized poly(methylsiloxane) with appendent Fréchet-type dendrons

A new kind of dendronized poly(methylsiloxane) (3a and 3b) with appendent Fre-chet-type poly(aryl ether) dendrons has been synthesized and characterized by GPC, DSC, TGA, fluorescence and UV-Vis spectra.     

Synthesis of sulfonimide-based dendrimers and dendrons possessing mixed 1 → 2 and 1 → 4 branching motifs

The synthesis of dendrimers and a chlorosulfo-dendron possessing a unique combination of 1?→?2 and 1?→?4 branching types is described. The procedure consists of a two-step preparation of 3,5-dinitrobenzene-1-sulfonyl chloride, which was used for the persulfonylation of p-toluidine and 4-(benzylthio)aniline. The obtained tetranitro compounds were reduced to the corresponding tetraamines. The latter were decorated with eight 4-toluene sulfonyl groups each to furnish the corresponding dendrimers. Oxidation of the dendrimer possessing a 4-(benzylthio)phenylene core with N-chlorosuccinimide resulted in the formation of a dendron with a sulfonyl chloride functionality at the focal point.