ROMP como um método versátil para a obtenção de materiais poliméricos diferenciados

Carvalho, Valdemiro P.; Ferraz, Camila P.; Sá, José Luiz Silva; Neto, Benedito dos Santos Lima

doi:10.1590/s0100-40422012000400026

Cited by 7 publications

(5 citation statements)

References 122 publications

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“…The yields or selectivity are achieved by tuning the choice of the catalyst with the reaction conditions [12]. In this way, the application of catalytic precursors, such as the Lima-Neto Ru-compounds synthesized for ROMP reactions [13][14][15][16], can be modulated for other purposes inside of the metathesis type.…”

Section: Of 11mentioning

confidence: 99%

Ethyl Linoleate Derivatives from Olefin Metathesis as a Function of the Starting Complex and Reactivity Conditions

Neta¹,

Silva²,

Carvalho³

et al. 2017

Preprint

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Olefin metathesis of ethyl linoleate (EL) was investigated under different conditions of substrate amount, temperature, and catalyst. Second-generation Grubbs catalyst (G2) was used in experiments at 20 and 50 ºC for 24 and 48h, whereas first-generation Grubbs catalyst (G1) and [RuCl2(PPh3)2perhydroazepine] (LN) were used in experiments at 50 ºC for 24h, with the latter also being investigated in the presence or absence of SnCl2 as co-catalyst. Catalytic products were analyzed for GC-MS and discussed in terms of relative percent of the metathesis products. With G2 as catalyst, GC-MS chromatograms were similar in all the amounts of EL investigated at 50 ºC for 24h, except for ethyl hexadec-9-enoate (compound K), which was obtained with different percentage as a function of EL amount (55% for 2 and 5 mL and 65% for 8 mL). An α,ω-dicarboxylic acid with m/z = 444.00 (compound L) was produced from the experiments at 50 ºC for 24h with similar percentage as a function of EL amount. However, the relative percentage of L changed with the increase of EL volume in the experiments at 20 ºC (ca. 18, 27, and 28%, with 2, 5, and 8 mL of EL, respectively). The olefin metathesis of EL conducted by G1 reached lower selectivity than that conducted by G2 for 24h at 50 ºC. Several intense peaks reached with G1 were similar to those obtained with G2, in addition to new peaks of medium intensity. Compound L showed higher m/z, similar to that presented with G2, but with lower relative proportion in the mixture. LN was inert for olefin metathesis of EL; however, it was activated in the presence of SnCl2 at 50 ºC for 24h. Different compounds and selectivity as a function of the catalyst type and reaction conditions were obtained.

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Section: Of 11mentioning

confidence: 99%

Ethyl Linoleate Derivatives from Olefin Metathesis as a Function of the Starting Complex and Reactivity Conditions

Neta¹,

Silva²,

Carvalho³

et al. 2017

Preprint

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“…In our research group, noncarbene ruthenium-based complexes have been studied for ROMP and ATRP. [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40] Many of these compounds have exhibited good activity, forming polymers and copolymers in high yields, with different thermal and morphological characteristics. Among these precatalysts, ruthenium amine compounds have produced polymers from norbornene (NBE) and norbornadiene (NBD) by ROMP and controlled methyl methacrylate (MMA) and styrene (St) polymerization via ATRP.…”

Section: Introductionmentioning

confidence: 99%

“…Ruthenium complexes bearing p ‐cymene with different types of ligands such as phosphines, Schiff bases, and N ‐heterocyclic carbenes with a general formula of [RuCl 2 ( p ‐cymene)(L)] have been investigated as ROMP or ATRP catalysts. In our research group, noncarbene ruthenium‐based complexes have been studied for ROMP and ATRP . Many of these compounds have exhibited good activity, forming polymers and copolymers in high yields, with different thermal and morphological characteristics.…”

Section: Introductionmentioning

confidence: 99%

Dual catalytic performance of arene‐ruthenium amine complexes for norbornene ring‐opening metathesis and methyl methacrylate atom‐transfer radical polymerizations

Cruz

Silva

Oliveira

et al. 2020

Applied Organom Chemis

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Arene ruthenium(II) complexes bearing the cyclic amines RuCl2(η6‐p‐cymene)(pyrrolidine)] (1), [RuCl2(η6‐p‐cymene)(piperidine)] (2), and [RuCl2(η6‐p‐cymene)(peridroazepine)] (3) were successfully synthesized. Complexes 1–3 were fully characterized by means of Fourier transform infrared, UV–visible, and NMR spectroscopy, elemental analysis, cyclic voltammetry, computational methods, and one of the complexes was further studied by single crystal X‐ray crystallography. These compounds were evaluated as catalytic precursors for ring‐opening metathesis polymerization (ROMP) of norbornene (NBE) and atom‐transfer radical polymerization (ATRP) of methyl methacrylate (MMA). NBE polymerization via ROMP was evaluated using complexes 1–3 as precatalysts in the presence of ethyl diazoacetate (EDA) under different [NBE]/[EDA]/[Ru] ratios, temperatures (25 and 50°C), and reaction times (5–60 min). The highest yields of polyNBE were obtained with [NBE]/[EDA]/[Ru] = 5000/28/1 for 60 min at 50°C. MMA polymerization via ATRP was conducted using 1–3 as catalysts in the presence of ethyl‐α‐bromoisobutyrate (EBiB) as initiator. The catalytic tests were evaluated as a function of the reaction time using the initial molar ratio of [MMA]/[EBiB]/[Ru] = 1000/2/1 at 95°C. The increase in molecular weight as function of time indicates that complexes 1–3 were able to mediate the MMA polymerization with an acceptable rate and some level of control. Differences in the rate of polymerization were observed in the order 3 > 2 > 1 for the ROMP and ATRP.

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“…Ring-opening metathesis polymerization (ROMP) of cyclic olefin has been an efficient method to develop polymers and copolymers for practical applications in different fields of science, including functionalized polymeric materials with advanced structures [1][2][3][4][5][6][7]. Pendant functional groups in the cyclic olefin, such as carboxylic or hydroxyl, are useful to be modified into many other groups for the development of unlike polymers [8,9].…”

Section: Introductionmentioning

confidence: 99%

Cross-link in norbornadiene-based polymers from ring-opening metathesis polymerization with pyrrolidine-based Ru complex

et al. 2017

Self Cite

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Ring-opening metathesis polymerization (ROMP) of norbornadiene (NBD) with [RuCl 2 (PPh 3) 2 (pyrrolidine)] as the starting complex was evaluated as a function of reaction time, solvent volume, and atmosphere type at 25°C. Quantitative yields of polyNBD were obtained either under inert argon atmosphere or in air, with 2 mL of CHCl 3 , for 30 min. Copolymerization of NBD with norbornene (NBE) resulted in 100-70% yield under argon, depending on the NBE/NBD molar ratio, and in 70% yield in air, with 2 mL, for 120 min. TGA, DSC, and DMA measurements and swelling tests supported the occurrence of cross-linking in homopolyNBD and in the copolymers isolated from polymers. SEM micrographs showed porous polymeric NBD materials with pores that decreased in size when increasing the amount of NBD in the starting reaction composition. Results from amine parent complexes when the amine was piperidine or perhydroazepine are also discussed, with high cross-linking degree from reaction with the pyrrolidine complex.

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ROMP como um método versátil para a obtenção de materiais poliméricos diferenciados

Cited by 7 publications

References 122 publications

Ethyl Linoleate Derivatives from Olefin Metathesis as a Function of the Starting Complex and Reactivity Conditions

Ethyl Linoleate Derivatives from Olefin Metathesis as a Function of the Starting Complex and Reactivity Conditions

Dual catalytic performance of arene‐ruthenium amine complexes for norbornene ring‐opening metathesis and methyl methacrylate atom‐transfer radical polymerizations

Cross-link in norbornadiene-based polymers from ring-opening metathesis polymerization with pyrrolidine-based Ru complex

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