Science of Synthesis

Wang, X.-Y.; Sun, X.-L., Science of Synthesis Knowledge Updates, (2020) 2, 471.

The cyclopolymerization of alka-1,ω-dienes to produce polymers with cyclic groups in repeating units is a facile and efficient approach for the synthesis of such cycloalkene polymers. For example, metallocene catalysts can catalyze the cyclopolymerization of hexa-1,5-diene to give poly[(cyclopentane-1,3-diyl)methylene]. It has long been of scientific interest to achieve stereochemical control over the cycloalkene polymer microstructure. For example, the cyclopolymerization of nonconjugated dienes using tridentate phenoxy–amine hafnium complex ‌67‌ was documented by Edson and Coates (‌Scheme 43‌).[‌65‌] The obtained poly[(cyclopentane-1,3-diyl)methylene] products ‌68‌ represented the first example of the formation of a highly cis-enriched microstructure with high selectivity for isotactic enchainment (α = 0.93–0.96).

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References