✍ Scribed by Dirk E. Heiser; Jun Okuda; Sandro Gambarotta; Rolf Mülhaupt
No coin nor oath required. For personal study only.
Summary: 1,3‐Cyclohexadiene (CHD) was homo‐ and copolymerized by means of diimine nickel complexes and various substituted titanium based half‐sandwich complexes activated with methylaluminoxane (MAO). Soluble polycyclohexadienes were produced with the constrained geometry catalyst [Me~2~Si(N^t^Bu)(Me~4~Cp)]TiCl~2~ (CBT) (Cp = cyclopentadienyl, Me = methyl). Only in the presence of CBT/MAO soluble high molecular weight CHD copolymers with ethylene were obtained. The CHD incorporation was varied between 0 and 12.3 mol‐%. According to NMR analysis the CHD/ethylene copolymerization is highly regioselective, accounting for exclusive formation of 1,4‐cyclohexene units randomly distributed in the polyethylene backbone.
^13^C NMR spectra of 1,4‐poly(1,3‐cyclohexadiene‐co‐ethylene) with 6.8 mol‐% CHD content in the copolymer.
magnified image^13^C NMR spectra of 1,4‐poly(1,3‐cyclohexadiene‐co‐ethylene) with 6.8 mol‐% CHD content in the copolymer.
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