An efficient method was developed for the preparation of macrocyclic carbohydrate/amino acid hybrids by macrocyclization with copper(I)-catalyzed 1,2,3-triazole formation. Methyl 2-amino-6-azido-3,4-di-O-benzoyl-2,6-dideoxy-beta-D-glucopyranoside was prepared and coupled to two different N-propiolyl dipeptides (propiolyl-Tyr-Tyr-OH and propiolyl-Arg(Mtr)-Tyr-OH) to obtain bifunctional molecules carrying one azido group and one terminal alkyne. These bifunctional molecules were cyclodimerized using Cu(I)-catalyzed 1,3-dipolar cycloaddition of azides and alkynes to form macrocycles containing two 1,2,3-triazoles. Various cyclization methods were evaluated, and the most efficient conditions were found to be CuI and N,N-diisopropylethylamine in CH3CN.

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Hydrophobic fumed silica dispersions in organic monomers were explored as a pore-forming system in polymer synthesis. The method developed provides a simple and effective way of controlling the pore size in highly cross-linked polymers. Fumed silica suspensions in divinylbenzene were polymerized with subsequent etching of the silica particles, therefore creating the porosity in the polymer. The resulting polymers are mesoporous materials, exhibiting an extremely narrow pore size distribution with an average pore size of about 100 Å, replicating the size of the nanofiller. BET surface areas were found appreciably high (∼350 m2/g). Furthermore, the rheological behavior of the prepolymerization mixtures was studied to elucidate the formation of the porous network and showed that a tridimensional network of particles is formed at a minimum silica fraction (Φ v ) of 0.08.

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