Group 4 dimethylsilylenebisamido complexes bearing the 6-[2-(diethylboryl)phenyl]pyrid-2-yl motif: synthesis and use in tandem ring-opening metathesis/vinyl-insertion copolymerization of cyclic olefins with ethylene.
Group 4 dimethylsilylenebisamido complexes bearing the 6-[2-(diethylboryl)phenyl]pyrid-2-yl motif: synthesis and use in tandem ring-opening metathesis/vinyl-insertion copolymerization of cyclic olefins with ethylene.
复制标题
带有 6-[2-(二乙基硼基)苯基]吡啶-2-基基序的第 4 族二甲基亚甲硅基双酰胺配合物：合成及其在环状烯烃与乙烯的串联开环复分解/乙烯基插入共聚中的应用。
作者：
Y. Zou;Dongren Wang;K. Wurst;Christa Kühnel;I. Reinhardt;U. Decker;V. Gurram;Sebnem Camadanli;M. Buchmeiser
合成了两种新的锆（IV）和铪（IV）基双酰胺配合物[ZrCl（2）{Me（2）Si（DbppN）（2）}（thf）]（9）和[HfCl（2）{Me（2）Si（DbppN）（2）}（thf）（2）]（10）（DbppN=6-[2-（二乙基硼基）苯基]吡啶-2-酰胺基）。它们的反应性进行了比较与模型预催化剂，不承担氨基硼烷基序。在用甲基铝氧烷活化时，预催化剂9和10在乙烯（E）的均聚反应中具有活性，产生高密度聚乙烯（HDPE）。在E与环戊烯（CPE）的共聚合中，例如通过9的作用，CPE的存在导致E的聚合活性的急剧增加，而CPE掺入保持接近或为零。在降冰片烯（NBE）与E的乙烯基插入共聚反应中，通过9的作用，得到了这两种单体的统计环烯烃共聚物。然而，在较高的NBE浓度下，9引起NBE与E的可逆开环易位（ROMP）/乙烯基插入聚合（VIP），导致形成通式为聚（NBE）（ROMP）-共-聚（NBE）（VIP）-共-聚（E）的多嵌段共聚物。预催化剂9的这种特殊特征，即诱导可逆的α-H消除/α-H加成反应的能力，归因于6-[2-（二乙基硼基）苯基]吡啶-2-基配体的独特作用。因此，缺乏该配体的模型预催化剂不具有诱导α-H消除/α-H加成反应的能力。不同的（11）B NMR位移的各种二乙基硼苯基吡啶-2-基胺和-酰胺允许在这些化合物中的B-N键的强度的排名。B-N键的这种强度与9/MAO在不同温度下产生聚（NBE）（ROMP）-共-聚（NBE）（VIP）-共-聚（E）的倾向相关。
Two novel Zr(IV)- and Hf(IV)-based bisamido complexes bearing the 6-[2-(diethylboryl)phenyl]pyrid-2-yl motif, that is, [ZrCl(2){Me(2)Si(DbppN)(2)}(thf)] (9) and [HfCl(2){Me(2)Si(DbppN)(2)}(thf)(2)] (10) (DbppN=6-[2-(diethylboryl)phenyl]pyridine-2-amido) have been prepared. Their reactivities have been compared with that of a model precatalyst that does not bear the aminoborane motif. Upon activation with methylalumoxane, precatalysts 9 and 10 are active in the homopolymerization of ethylene (E) yielding high-density polyethylene (HDPE). In the copolymerization of E with cyclopentene (CPE), for example by the action of 9, the presence of CPE resulted in a dramatic increase in the polymerization activity of E, while CPE incorporation remained close to or at zero. In the vinyl-insertion copolymerization of norborn-2-ene (NBE) with E by the action of 9, statistical cyclic olefin copolymers of these two monomers were obtained. At higher NBE concentrations, however, 9 gave rise to reversible ring-opening metathesis (ROMP)/vinyl-insertion polymerization (VIP) of NBE with E, resulting in the formation of multi-block copolymers of the general formula poly(NBE)(ROMP)-co-poly(NBE)(VIP)-co-poly(E). This particular feature of precatalyst 9, that is, the ability to induce a reversible α-H elimination/α-H addition reaction, is attributed to the unique role of the 6-[2-(diethylboryl)phenyl]pyrid-2-yl ligand. Accordingly, a model precatalyst lacking this ligand does not have the ability to induce α-H elimination/α-H addition reactions. The different (11)B NMR shifts of various diethylborylphenylpyrid-2-ylamines and -amides permit a ranking of the strengths of the B-N bonds in these compounds. This strength of the B-N bond is correlated with the propensity of 9/MAO to produce poly(NBE)(ROMP)-co-poly(NBE)(VIP)-co-poly(E) at different temperatures.
影响因子：
16.6
作者：
Buchmeiser, Michael R.;Camadanli, Sebnem;Reinhardt, Ingrid
通讯作者：
Reinhardt, Ingrid