Amphiphilic reactions by means of exceptionally bulky organoaluminum reagents. Rational approach for obtaining unusual equatorial, anti-Cram, and 1,4 selectivity in carbonyl alkylation
A living polymerization method in which an organic aluminum compound having a bulky substituent group is used as a cocatalyst in the living polymerization of a (meth)acrylic acid ester, an epoxide or a lactone in the presence of a metal porphyrin complex as a polymerization initiator.
Amphiphilic reactions by means of exceptionally bulky organoaluminum reagents. Rational approach for obtaining unusual equatorial, anti-Cram, and 1,4 selectivity in carbonyl alkylation
Sterically Hindered Aluminum Alkyls: Weakly Interacting Scavenging Agents of Use in Olefin Polymerization
作者:Russell A. Stapleton、Abdulaziz Al-Humydi、Jianfang Chai、Brandon R. Galan、Scott Collins
DOI:10.1021/om060474s
日期:2006.10.1
Stericallyhindered aluminum methyl compounds derived from reaction of hindered phenols with AlMe3 (i.e., MeAl(BHT)2 and MeAl(BHT*)2; BHT = 2,6-di-tert-butyl-4-methylphenoxide; BHT* = 2,4,6-tri-tert-butylphenoxide) are useful scavenging agents in olefin polymerization using metallocene catalysts. They do not, or only slowly, react with activators such as B(C6F5)3 or [Ph3C][B(C6F5)4] at 25 °C, nor do
受阻酚与AlMe 3(即,MeAl(BHT)2和MeAl(BHT *)2; BHT = 2,6-二叔丁基-4-甲基苯酚; BHT * = 2 (4,6-三叔丁基苯氧化物)是在使用茂金属催化剂的烯烃聚合中有用的清除剂。它们不会或仅在25°C下与活化剂如B(C 6 F 5)3或[Ph 3 C] [B(C 6 F 5)4 ]缓慢反应,也不会与或与之活化或反应衍生自茂金属二烷基的金属茂离子对和这些活化剂。AlMe的混合物由图3可知,对于容易与MeAl(BHT)2的水解产物BHT-H反应的催化剂而言,MeAl(BHT)2的过量被证明是有利的。乙烯聚合实验确定,在明显过量的MeAl(BHT)2存在的情况下,AlMe 3只会略微抑制[Cp 2 ZrMe] [MeB(C 6 F 5)3 ]的活性。光谱研究表明,AlMe 3与MeAl(BHT)2处于平衡状态,形成Me 2 Al(BHT)。在低温下使用13 C