Angew. Chem. Int. Ed., 2017, 56(10), 2714-2719
Abstract
Styrene
underwent unprecedented coordination–insertion copolymerization with naked
polar monomers (ortho-/meta-/para-methoxystyrene) in the
presence of a pyridyl methylene fluorenyl yttrium catalyst. High activity
(1.26×106 g?molY?1 h?1) and
excellent syndioselectivity were observed, and high-molecular-weight copolymers
(24.6×104 g?mol?1) were obtained. The insertion rate of
the polar monomers could be adjusted in the full range of 0–100?% simply by
changing the loading of the polar styrene monomer. Strikingly, the copolymers
had tapered, gradient, and even random sequence distributions, depending on the
position of the polar methoxy group on the phenyl ring and thus on its mode of
coordination to the active metal center, as shown by tracking the
polymerization process and DFT calculations.
文章鏈接：http://onlinelibrary.wiley.com/doi/10.1002/anie.201611066/full