دورية أكاديمية

Suzuki–Miyaura Catalyst-Transfer Condensation Polymerization for the Synthesis of Polyphenylene with Ester Side Chain by Using Stable, Reactive 1,1,2,2-Tetraethylethylene Glycol Boronate (B(Epin)) Monomer

التفاصيل البيبلوغرافية
العنوان: Suzuki–Miyaura Catalyst-Transfer Condensation Polymerization for the Synthesis of Polyphenylene with Ester Side Chain by Using Stable, Reactive 1,1,2,2-Tetraethylethylene Glycol Boronate (B(Epin)) Monomer
المؤلفون: Reo Nitto, Yoshihiro Ohta, Tsutomu Yokozawa
سنة النشر: 2024
مصطلحات موضوعية: Biophysics, Biochemistry, Medicine, Microbiology, Cell Biology, Neuroscience, Evolutionary Biology, Biological Sciences not elsewhere classified, Chemical Sciences not elsewhere classified, tetraethylethylene glycol boronate, model reactions showed, mass spectrum showed, ester side chain, assisted laser desorption, affording mainly polymers, successive repeat units, poor catalyst transfer, 2b , 2a , donor initiator unit, n , 0 , transfer condensation polymerization, monomer (< b, 1 , acceptor monomer unit, 3 , 1 , repeat unit, acceptor monomer
الوصف: Suzuki–Miyaura catalyst-transfer condensation polymerization (CTCP) of 4-bromo-2,5-dihexyloxycarbonylphenylboronic acid ester ( 2 ) as an acceptor monomer was investigated. The polymerization of the boronic acid pinacol ester (Bpin) monomer ( 2a ) was first conducted in the presence of t Bu 3 P-ligated tolyl–Pd-Br initiator 1 and CsF/18-crown-6 as a base, affording mainly polymers with H/H ends. We thought that the unsuccessful CTCP of 2a might be due to (1) poor catalyst transfer from the donor initiator unit to the acceptor monomer unit, (2) strong coordination of the Pd catalyst to the alkoxycarbonyl groups on successive repeat units, or (3) nonplanarity of the π-face of the backbone owing to the steric effect of the alkoxycarbonyl groups in the repeat unit. However, model reactions showed that the Pd catalyst successfully underwent intramolecular catalyst transfer, ruling out these possibilities. We then replaced 2a with B(Epin) monomer 2b , which is more stable than 2a . In the polymerization of 2b , the M n value increased in proportion to the monomer conversion and feed ratio of [ 2b ] 0 /[ 1 ] 0 and the molecular weight distribution remained narrow. The matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrum showed a series of peaks due to the polymer with Tolyl/H ends. After end-capping of the polymer with 4-methoxyphenylboronic acid, the 1 H NMR spectrum exhibited signals of both end groups. These results indicate that the polymerization of 2b proceeded according to the CTCP mechanism.
نوع الوثيقة: article in journal/newspaper
اللغة: unknown
العلاقة: https://figshare.com/articles/journal_contribution/Suzuki_Miyaura_Catalyst-Transfer_Condensation_Polymerization_for_the_Synthesis_of_Polyphenylene_with_Ester_Side_Chain_by_Using_Stable_Reactive_1_1_2_2-Tetraethylethylene_Glycol_Boronate_B_Epin_Monomer/25038622Test
DOI: 10.1021/acs.macromol.3c02003.s001
الإتاحة: https://doi.org/10.1021/acs.macromol.3c02003.s001Test
https://figshare.com/articles/journal_contribution/Suzuki_Miyaura_Catalyst-Transfer_Condensation_Polymerization_for_the_Synthesis_of_Polyphenylene_with_Ester_Side_Chain_by_Using_Stable_Reactive_1_1_2_2-Tetraethylethylene_Glycol_Boronate_B_Epin_Monomer/25038622Test
حقوق: CC BY-NC 4.0
رقم الانضمام: edsbas.805CA363
قاعدة البيانات: BASE