Controlled ring‐opening homo‐ and copolymerization of ɛ‐caprolactone and d, l‐lactide by iminophenolate aluminum complexes: An efficient approach toward well‐defined macromonomers. Issue 9 (6th February 2014)

• Record Type: Journal Article
• Authors: Zaitsev, Kirill V.; Piskun, Yulia A.; Oprunenko, Yuri F.; Karlov, Sergey S.; Zaitseva, Galina S.; Vasilenko, Irina V.; Churakov, Andrei V.; Kostjuk, Sergei V.
• Is Part Of: Journal of polymer science. Volume 52:Issue 9(2014:May)
• Page Start: 1237
• Page End: 1250
• Publication Date: 2014-02-06
• Subjects: 547
• DOI: 10.1002/pola.27110
• Languages: English
• ISSNs: 0887-624X

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>The aluminum complexes containing two iminophenolate ligands of the type (<italic>p</italic>‐XC<sub>6</sub>H<sub>4</sub>NCHC<sub>6</sub>H<sub>4</sub>O‐<italic>o</italic>)<sub>2</sub>AlR' (R′=Me (<bold>3, 4</bold>) or R′=O(CH<sub>2</sub>)<sub>4</sub>OCH=CH<sub>2</sub> (<bold>5, 6</bold>), X=H (<bold>3, 5</bold>), F(<bold>4, 6</bold>)) were synthesized and characterized by <sup>1</sup>H, <sup>13</sup>C NMR spectroscopy, and X‐ray crystallography. The reaction of AlMe<sub>3</sub> with two equivalents of substituted iminophenols gave five‐coordinated {ONR}<sub>2</sub>AlMe (<bold>3, 4</bold>) complexes. Subsequent reaction of these methyl complexes with unsaturated alcohol, HO(CH<sub>2</sub>)<sub>4</sub>OCH=CH<sub>2</sub>, resulted in target compounds <bold>5</bold> and <bold>6</bold> in a good yield. It was shown that the complexes (<bold>3</bold>‐<bold>6</bold>) are monomeric in solution (NMR) and in solid state (X‐ray analysis). The catalytic activity of the complexes <bold>5</bold> and <bold>6</bold> towards ring‐opening polymerization (ROP) of ɛ‐caprolactone and <sc>d, l</sc>‐lactide was assessed. Complex <bold>5</bold> showed higher activity as compared with <bold>6</bold>, while both of these catalysts induced controlled homo‐ and copolymerization to afford the macromonomers with high content of vinyl ether end groups (<italic>F</italic><sub>n</sub> > 80%) in a broad range of molecular weights (<italic>M</italic><sub>n</sub> = 4000–30, 000 g mol<sup>−1</sup>) with relatively narrow MWD (<italic>M</italic><sub>w</sub>/<italic>M</italic><sub>n</sub> = 1.1–1.5). © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. <bold>2014</bold>, <italic>52</italic>, 1237–1250</p> </abstract>