Titanium-salen complexes as initiators for the ring opening polymerisation of rac-lactide

被引：115
作者：
Gregson, Charlotte K. A. [1 ]
Blackmore, Ian J. [1 ]
Gibson, Vernon C. [1 ]
Long, Nicholas J. [1 ]
Marshall, Edward L. [1 ]
White, Andrew J. P. [1 ]
机构：
[1] Univ London Imperial Coll Sci Technol & Med, Dept Chem, London SW7 2AZ, England
来源：
DALTON TRANSACTIONS | 2006年 / 25期
关键词：
D O I：
10.1039/b518266b
中图分类号：
O61 [无机化学];
学科分类号：
070301 ; 081704 ;
摘要：
A family of bis(iso-propoxide) titanium(IV) complexes supported by tetradentate Schiff base ( salen) ligands has been synthesised and characterised, including a structural determination of N,N'-bis(6'-methylenimino-2',4'-di-tert-butylphenoxy)cyclohexyl-(1R, 2R)-diamino titanium(IV) bis(iso-propoxide). Their suitability for initiating the ring-opening polymerisation of rac-lactide has been investigated. Polymerisation activities are shown to correlate with the electronic properties of the substituents within the salen ligand. In contrast to aluminium-salen initiators, electron-withdrawing substituents on the Schiff base ligand have a detrimental influence upon polymerisation activities, whereas the use of electron-donating alkoxy-functionalised ligands has allowed the highest recorded activity to date for a titanium-based initiator.
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收藏
页码：3134 / 3140
页数：7
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