Ethylene Oligomerization and Polymerization by Palladium(II) Methyl Complexes Supported by Phosphines Bearing a Perchlorinated 10-Vertex closo -Carborane Anion Substituent
Ethylene Oligomerization and Polymerization by Palladium(II) Methyl Complexes Supported by Phosphines Bearing a Perchlorinated 10-Vertex closo -Carborane Anion Substituent
复制标题
带有全氯 10 顶点近碳硼烷阴离子取代基的膦负载的钯 (II) 甲基配合物的乙烯齐聚和聚合
DOI：
10.1021/acs.organomet.8b00772
复制
发表时间：
2018
期刊：
影响因子：
2.8
通讯作者：
Lavallo, Vincent
中科院分区：
文献类型：
--
作者：
Kleinsasser, Jack F.;Reinhart, Erik D.;Estrada, Jess;Jordan, Richard F.;Lavallo, Vincent
本文报道了一系列两性离子钯甲基配合物（κ2-P，Cl-PR_2CB_9 Cl_9）PdMe（THF）（7，R =iPr;8，R = Ph）和（κ2-P，O-P（o-OMe-Ph）_2CB_9 Cl_9）PdMe（THF）（9）的合成和乙烯反应活性。配合物7和8将乙烯（23 °C，2atm）低聚成具有约100个TOF的C4-C10烯烃的Schulz-Flory分布。8000和1800吨/年h，分别为0.8和0.8。比Jordan和Piers报道的生成丁烯的类似（κ2-P，F-邻-PPh 2C 6 H4 BF 3）PdMe（L）（L =吡啶或可力丁）体系的活性高4倍。络合物9与乙烯反应产生聚乙烯蜡（Mnca. 1000，加的斯。1.5)其类似于商业费-托蜡。7 - 9的活性与乙烯压力和B（C6 F5）3的存在无关，表明催化剂的静止状态是相应的（PR 2CB 9 Cl 9）PdR（H2 C = CH 2）加合物。低聚物/聚合物产物的分子量与乙烯压力无关，这与缔合链转移机理一致。9与乙烯反应生成相应的乙烯络合物（κ2-P，O-P（o-OMe-Ph）2CB 9 Cl 9）PdMe（H2 C <$CH2），它在−20 °C下插入乙烯，势垒（ΔG <$插入）为18.1 kcal/mol。
The synthesis and ethylene reactivity of the zwitterionic Pd methyl complexes (κ2-P,Cl-PR2CB9Cl9)PdMe(THF) (7, R =iPr;8, R = Ph) and (κ2-P,O-P(o-OMe-Ph)2CB9Cl9)PdMe(THF) (9), which contain the first phosphines appended with anionic 10-vertex perchlorinatedcloso-carboranes, are described. Complexes7and8oligomerize ethylene (23 °C, 2 atm) to a Schulz–Flory distribution of C4–C10olefins with TOFs of ca. 8000 and 1800 t.o./h, respectively.8is ca. 4 times more active than the analogous (κ2-P,F-ortho-PPh2C6H4BF3)PdMe(L) (L = pyridine or collidine) system reported by Jordan and Piers, which produces butenes. Complex9reacts with ethylene to yield polyethylene wax (Mnca. 1000,Đca. 1.5) that is similar to commercial Fischer–Tropsch waxes. The activities of7–9are independent of ethylene pressure and the presence of B(C6F5)3, suggesting that the catalyst resting state is the corresponding (PR2CB9Cl9)PdR(H2C═CH2) adduct. The molecular weights of the oligomer/polymer products are independent of ethylene pressure, which is consistent with an associative chain transfer mechanism. Reaction of9with ethylene generates the corresponding ethylene complex (κ2-P,O-P(o-OMe-Ph)2CB9Cl9)PdMe(H2C═CH2), which inserts ethylene at −20 °C with a barrier (ΔG⧧insertion) of 18.1 kcal/mol.