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Poly(diaryl)stannanes were prepared by the dehydropolymerization of secondary hydrostannanes Ar2SnH2 with dimethylzirconocene catalyst. At room temperature, H(Ar2Sn)nH polystannanes (Ar ) p-t Bu-C6H4, p-n Hex-C6H4, o-Et-C6H4, o-Et-p-n BuO-C6H3, p-n BuO-C6H4, p-(Me3Si)2N-C6H4) exhibit λmax values attributed to σ f σ* transitions in the range 430-506 nm. These values vary according to the polymer molecular weights and are independent of temperature between -20 and 90 °C. A sample of poly[bis(o-ethyl-p-n butoxylphenyl)]stannane exhibits a strong UV-vis absorption at 506 nm (tailing to ca. 550 nm), which corresponds to the smallest band gap yet observed for a group 14, σ-conjugated polymer. The H(Ar2Sn)nH polystannanes undergo photodecomposition in solution to give a mixture of the cyclohexamer and the cyclo-pentamer. Thermal gravimetric analyses for the polymers suggest that H(Ar2-Sn)nH polystannanes are thermally stable and have onset temperatures for thermal decomposition in the range 180-320 °C, under both nitrogen and air. The H(Ar2Sn)nH polystannanes undergo clean thermal decompositions to elemental tin (under nitrogen) or tin oxide (under oxygen or air), as shown by bulk pyrolysis.

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Chiral stationary phases (CSPs) containing L-proline indananilide chiral selectors attached through a multivalent dendritic linker to monodisperse macroporous poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate) beads have been prepared using two different approaches. The convergent method involves the preparation of ligands in solution and their subsequent attachment to the support. The divergent approach is based on the stepwise "on-bead" formation of the linker using methods that are typical of solid-phase synthesis. While the convergent CSPs feature well-defined ligands, their loading is relatively low. In contrast, the divergent technique affords CSPs with higher loading but with more limited control over precise ligand architecture. Excellent enantioselectivities characterized by separation factors of up to 31 were achieved for the separation of racemic N-(3,5-dinitrobenzoyl)-alpha-amino acid alkyl amides with these new CSPs under normal-phase HPLC conditions.