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Cryptochiral isotactic polystyrene induces the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde, affording the enantioenriched pyrimidyl alkanol with the corresponding absolute configuration to that of polystyrenes in conjunction with asymmetric autocatalysis.

A thermally robust zirconium catalyst containing a tetradentate bis(phenolate) ligand of the (OSSO)-type polymerizes styrene and butadiene in living fashion. The activity follows the order Zr > Hf > Ti. Low polydispersities of the resulting isotactic poly styrenes (PD < 1.10) can be achieved at room temperature, while butadiene is polymerized at temperatures as high as 90 °C to give predominantly trans -1,4-polymer. This allows effi cient preparation of isotactic polystyrene-block -polybutadiene copolymers (iPS-b -PBD).

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p-(2,2′-Diphenylethyl)styrene (DPES) was polymerized with the homochiral postmetallocene catalyst dichloro{trans-1,2-dithiocyclohexanediyl-2,2′-bis(4,6-di-tert-butylphenolato)}titanium/MAO. Optically active isotactic polymers were obtained by a controlled reduction of the molecular weight, employing diethylzinc as CTA. Polymers with molecular weights below Mn of 50,000 g mol−1 showed specific rotation values ([α]23D) between ±0.2 and 2.2.