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    Application of well-defined ruthenium alkylidenes to the ROMP of norbornene derivatives: Methoxyphenyl-substituted polynorbornene dicarboximides
    (Elsevier Science Bv, 2011) Cetinkaya, Sevil; Ozker, Taner; Bayram, Rifat
    The applicability of ruthenium alkylidenes as initiators in the ring opening metathesis polymerization (ROMP) of methoxyphenyl group containing norbornene derivatives has been investigated. The synthesis and polymerization of exo-N-4-methoxyphenyl-oxanorbornene-5,6-dicarboximide (MeOPhONDI) and exo-N-4-methoxyphenyl-norbornene-5,6-dicarboximide (MeOPhNDI) are reported. Polynorbornene derivatives were obtained via ROMP using first- and second-generation ruthenium alkylidene initiators. The structural properties of the polynorbornene derivatives were analyzed by NMR, DSC and GPC. Analyses of the polymer microstructures indicate that polymers contain trans stereoconfiguration of the double bonds (55-86% trans-content). The glass transition temperatures of the polymers obtained from exo-monomers are higher than 211 degrees C. (C) 2010 Elsevier B.V. All rights reserved.
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    Influence of ruthenium alkylidene complexes bearing tricyclohexylphosphine or 3-bromopyridine ligand on the properties of fluorine containing polymers
    (Springer, 2013) Cetinkaya, Sevil; Ozker, Taner; Kaya, Pembe Hulya; Yasar, Emine; Bayram, Rifat
    The catalytic performance of ruthenium alkylidene complexes bearing tricyclohexylphosphine or 3-bromopyridine ligand in the ring opening metathesis polymerization (ROMP) of fluorine containing monomers, exo-N-4-fluorophenyl-7-oxanorbornene-5,6-dicarboximide (FPhONDI) and exo-N-4-fluorophenyl-norbornene-5,6-dicarboximide (FPhNDI) was investigated. Pure monomers were subjected to ROMP with RuCl2(PCy3)(2)(CHPh) (I), RuCl2(PCy3)(H(2)IMes)(CHPh) (II), RuCl2(3-Br-py)(2)(PCy3)(CHPh) (III) and RuCl2(3-Br-py)(2)(H(2)IMes)(CHPh) (IV). The polymers were fully characterized using NMR, DSC, SEM and GPC. Catalysts I-IV displayed significant ROMP activity, allowing for the synthesis of the corresponding polymers with polydispersity indices (PDIs) in the range of 1.4-4.0. High molecular weight polymers (Mw up to 4.95 x10(5)) were prepared in yields up to 90 %, depending on the initiator and monomer used.
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    Oksanorbornen türevlerinin rutenyum kompleks-katalizli halka açılımı metatez tepkimelerinin incelenmesi
    (Kırıkkale Üniversitesi, 2009) Bayram, Rifat; Eren, Sevil Çetinkaya
    Son on yıldır olefin metatez katalizörleri ve uygulamaları etkileyici gelişmeler göstermiştir. Özellikle rutenyum alkiliden komplekslerinin keşfi metatez alanında büyük etki yaratmıştır.Bu çalışmada, rutenyuma dayalı Grubbs tipi katalizörlerin (birinci ve ikinci üretim) ekzo-N-substitue-fenil-oksanorbornen türevlerine uygulanabilirliği araştırıldı. Oksanorbornen türevlerinin sentezi ve bunların halka açılımı yöntemi ile polimerizasyonu (ROMP) gerçekleştirildi. Elde edilen polimerler SEM, NMR, DSC ve GPC ile karakterize edildi. Monomerlerin halka açılımı metatez polimerizasyonu yüksek molekül ağırlıklı ve trans karakterli çift bağlara sahip polimerlerin oluşumunu sağlamıştır.Anahtar Kelimeler: Metatez, ROMP, Rutenyum alkiliden, Polinorbornen dikarboksimid
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    Synthesis of High-T-g Polymers via ROMP of Oxanorbornene Dicarboximides with Halogen Groups
    (Wiley-Blackwell, 2010) Cetinkaya, Sevil; Bayram, Rifat
    This paper describes the synthesis of exo-N-phenyl-7-oxanorbornene-5, 6-dicarboximides with different substituents at para positions in the aromatic ring and their polymerization by ring-opening metathesis polymerization (ROMP) leading to high-T-g polymers. Exo-N-4-chlorophenyl-7-oxanorbornene-5,6-dicarboximide (ClPhONDI, 3a), exo-N-4-bromophenyl-7-oxanorbornene-5,6-dicarboximide (BrPhONDI, 3b), and exo-N-4-iodophenyl-7-oxanorbomene-5,6-dicarboximide (1PhONDI, 3c) monomers were synthesized. Polynorbornene dicarboximides were obtained via ROMP using a first-generation ruthenium alkylidene catalyst, Cl-2(PCy3)(2)Ru(=CHPh). The resulting amorphous polymers with trans configuration of the double bonds were characterized by NMR, SEM, DSC, and GPC. (C) 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:36-43, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20576