Living 3,4-(Co)Polymerization of Isoprene/Myrcene and One-Pot Synthesis of a Polyisoprene Blend Catalyzed by Binuclear Rare-Earth Metal Amidinate Complexes
Living 3,4-(Co)Polymerization of Isoprene/Myrcene and One-Pot Synthesis of a Polyisoprene Blend Catalyzed by Binuclear Rare-Earth Metal Amidinate Complexes
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双核稀土金属脒配合物催化异戊二烯/月桂烯活性3,4-(Co)聚合及一锅法合成聚异戊二烯共混物
DOI：
10.1002/chem.201804944
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发表时间：
2019
期刊：
影响因子：
--
通讯作者：
Lixin Zhang
中科院分区：
文献类型：
--
作者：
Xiaying Yu;Meng Li;Jianquan Hong;Xigeng Zhou;Lixin Zhang
合成并表征了单脒基钇配合物C4 H9 C（NR）2 Y（o-CH 2C 6 H4 NMe 2）2（R= 2，6-iPr 2C 6 H3）和一系列带有桥联脒基配体的双核稀土金属配合物[（RN）2C（CH 2）4C（NR）2][RE{CH 2C 6 H4（o-NMe 2）}2]2（R= 2，6-iPr 2C 6 H3，RE=Y，Lu，Sc）。研究了这些配合物在助催化剂[Ph 3C][B（C6 F5）4]存在下对共轭二烯如异戊二烯和月桂烯的（共）聚合的催化行为。这些催化体系在活性（共）聚合中显示出令人印象深刻的高活性和3，4-区域选择性。双核桥联脒基钇催化体系不仅在已报道的异戊二烯3，4-聚合催化体系中表现出最高的活性，而且允许在−20至80 °C以活性方式稳定聚合。与单核类似物的3，4-选择性急剧下降相比，双核催化体系在80 °C下仍显示出中等的3，4-选择性。此外，通过添加过量的AlMe 3对活性脒基钇物种进行原位改性，建立了用于含有3，4-和1，4-聚异戊二烯（PIP）的聚合物共混物的简便的一锅法合成策略。
Mononuclear amidinate yttrium complex C4H9C(NR)2Y(o‐CH2C6H4NMe2)2(R=2,6‐iPr2C6H3) and a series of binuclear rare‐earth metal complexes bearing a bridged amidinate ligand [(RN)2C(CH2)4C(NR)2][RE{CH2C6H4(o‐NMe2)}2]2(R=2,6‐iPr2C6H3, RE=Y, Lu, Sc) were synthesized and fully characterized. The catalytic behavior of these complexes for (co)polymerization of conjugated dienes such as isoprene and myrcene in the presence of co‐catalyst [Ph3C][B(C6F5)4] was investigated. These catalytic systems show impressively high activity and 3,4‐regioselectivity in living (co)polymerization. The binuclear bridged amidinate yttrium catalytic system not only exhibits the highest activity among the reported catalytic systems for 3,4‐polymerization of isoprene but also allows the steady polymerization in a living manner from −20 to 80 °C. Compared with the dramatic drop of 3,4‐selectivity for the mononuclear analogue, the binuclear catalytic system still shows moderate 3,4‐selectivity at 80 °C. Moreover, a facile one‐pot synthetic strategy for a polymer blend containing 3,4‐ and 1,4‐polyisoprene (PIP) was established through the in situ modification of the active amidinate yttrium species by addition of an excess amount of AlMe3.