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Updated: Sep 4, 2026

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyl(tropone)iron
Published on: August 12, 2019
α-Diimine Iron(II) Complexes Featuring Axial Anagostic Interaction: A High Cis-1,4-Selective System for 1,3-Butadiene
Lijia Liu1, Xiaohua Wang1, Xiaohui Kang2
1State Key Laboratory of Advanced Optical Polymer and Manufacturing Technology, Key Laboratory of Rubber-Plastics, Ministry of Education, Qingdao University of Science & Technology, Qingdao266042, China.
Abstract:
Iron complexes are renowned for promoting vinyl-selective polymerization of diene monomers, whereas systems capable of delivering high cis-1,4-selectivity remain relatively scarce. Herein, a series of α-diimine FeCl2 complexes featuring axial Fe...H-C anagostic interactions were synthesized and evaluated for 1,3-butadiene polymerization. Upon activation with AlR3/[Ph3C][B(C6F5)4], these complexes produce polybutadienes with much-enhanced cis-1,4-selectivity of up to 86%. Notably, the cis-1,4-selectivity remains largely insensitive to steric variations at distal ligand positions across the examined series (H vs tBu, cis-1,4-content of 81-84%), showing clear contrast to conventional α-diimine iron systems (cis-1,4-content <50%).
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