Alkaline earth metal complexes of a chiral polyether as initiator for the ring-opening polymerization of lactide
作者:Julien P. Davin、Jean-Charles Buffet、Thomas P. Spaniol、Jun Okuda
DOI:10.1039/c2dt31309j
日期:——
A chiral, tetradentate polyether ligand with a trans-1,2-cyclohexanediyl backbone, bis(methoxyethoxy)-trans-1,2-cyclohexane (5), was synthesized as both a racemate and the (S,S) enantiomer. 5 was found to form stable adducts with alkaline earth metal amides [MN(SiMe3)2}2(thf)x] (M = Mg (x = 0), Ca (x = 2) and Sr (x = 2/3)), [CaN(SiHMe2)2}2(thf)] as well as with hydrocarbyl compounds [Mg(CH2SiMe3)2] and [Ca(η3-C3H5)2]. X-ray diffraction study of the bis(amide) [((S,S)-5)CaN(SiMe3)2}2] and of the bis(allyl) [(rac-5)Ca(η3-C3H5)2] was performed. The complexes obtained were tested as initiators for the ring-opening polymerization of meso-, racemic and L-lactide.
一种以反式-1,2-环己二基为骨架的手性四价聚醚配体--双(甲氧基乙氧基)-反式-1,2-环己烷(5)被合成为外消旋体和(S,S)对映体。发现 5 与碱土金属酰胺 [MN(SiMe3)2}2(thf)x](M = Mg (x = 0)、Ca (x = 2) 和 Sr (x = 2/3))、[CaN(SiHMe2)2}2(thf)] 以及烃基化合物 [Mg(CH2SiMe3)2] 和 [Ca(η3-C3H5)2]形成稳定的加合物。对双(酰胺)[((S,S)-5)CaN(SiMe3)2}2]和双(烯丙基)[(rac-5)Ca(η3-C3H5)2]进行了 X 射线衍射研究。所获得的复合物被测试用作中生代、外消旋和 L-内酰胺开环聚合的引发剂。