First Acyclic Diene Metathesis Polymerization Under Biphasic Conditions Using a Dicationic Ruthenium Alkylidene: Access to High‐Molecular‐Weight Polymers with Very Low Ruthenium Contamination. Issue 2 (19th September 2014)

• Record Type: Journal Article
• Authors: Zhao, Jing; Wang, Dongren; Autenrieth, Benjamin; Buchmeiser, Michael R.; Frey, H.; Mecking, S.
• Is Part Of: Macromolecular rapid communications. Volume 36:Issue 2(2015:Jan.)
• Page Start: 190
• Page End: 194
• Publication Date: 2014-09-19
• Subjects: Macromolecules -- Periodicals; Polymers -- Periodicals; Chemistry -- Periodicals; 547.705
• DOI: 10.1002/marc.201400413
• Languages: English
• ISSNs: 1022-1336

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The acyclic diene metathesis (ADMET) polymerization of 6‐hydroxy‐1, 10‐undecadiene (<bold>M1</bold>) and 6‐acetoxy‐1, 10‐undecadiene (<bold>M2</bold>) by the action of two different catalysts, i.e., the second‐generation Grubbs‐Hoveyda system ([RuCl<sub>2</sub>(IMesH<sub>2</sub>)(CH‐2‐(2‐PrO‐C<sub>6</sub>H<sub>4</sub>)]) (<bold>1</bold>) and the dicationic ruthenium alkylidene [Ru(DMF)<sub>3</sub>(IMesH<sub>2</sub>)(CH‐2‐(2‐PrO‐C<sub>6</sub>H<sub>4</sub>)] (<bold>2</bold>, IMesH<sub>2</sub> = 1, 3‐dimesitylimidazolin‐2‐ylidene) is reported. Biphasic conditions using 1‐butyl‐2, 3‐dimethylimidazolium tetrafluoroborate ([BDMIM<sup>+</sup>BF<sub>4</sub><sup>−</sup>]) and 1, 2, 4‐trichlorobenzene (TCB) are applied. Under the chosen conditions (<italic>T</italic> = 75 °C, 20 mbar), the use of catalyst <bold>1</bold> results only in the formation of low‐molecular‐weight polymers (<inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh372v5r1c" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:dummy:marc201400413:equation:marc201400413-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mover accent="true"><mml:mi>M</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mi mathvariant="normal">n</mml:mi></mml:msub></mml:mrow></mml:math></alternatives></inline-formula> ≤ 10 000 g mol<sup>−1</sup>), while catalyst <bold>2</bold> allows for the high yield synthesis of high‐molecular‐weight polymers (<inline-formula><alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgh372v5r64" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:dummy:marc201400413:equation:marc201400413-math-0002" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mover accent="true"><mml:mi>M</mml:mi><mml:mo>¯</mml:mo></mml:mover><mml:mi mathvariant="normal">n</mml:mi></mml:msub></mml:mrow></mml:math></alternatives></inline-formula> ≤ 40 000 g mol<sup>−1</sup>, yields ≤ 99%). Irrespective of the catalyst used, all polymers display a high <italic>trans</italic>‐content (>95%). Notably, Ru‐contamination of the target polymers without any additional purification is as low as 1.2 ppm with catalyst <bold>2</bold>. Together with the high yields and high molecular weights, the low Ru‐contaminations clearly illustrate the advantages of the biphasic setup. <boxed-text content-type="graphic" position="anchor" orientation="portrait"><graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgh372v5t2z" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></boxed-text></p> </abstract>