Mechanistically designed dual-site catalysts for the alternating ROMP of norbornene and cyclooctene
Mechanistically designed dual-site catalysts for the alternating ROMP of norbornene and cyclooctene
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DOI：
10.1021/om700321a
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发表时间：
2007-07-02
期刊：
影响因子：
2.8
通讯作者：
Chen, Peter
中科院分区：
文献类型：
--
作者：
Bornand, Marc;Torker, Sebastian;Chen, Peter
通过对表征良好的碳钌配合物进行烯烃复分解反应的机理研究，合理设计和合成了一种改性的、不对称的“第一代”催化剂，与具有对称配体的第一代或第二代系统相比，它将两个环烯烃单体的混合物转化为一个很大程度上交替的共聚物。均相催化剂在每次周转时在一种以上状态之间转换的机理概念是一般的。通过质谱，核磁共振和x射线晶体学测定的配合物结构揭示了一些意想不到的特征，这些特征解释了共聚物中的序列错误。
Mechanistic work on the olefin metathesis reaction by well-characterized ruthenium carbene complexes led to the rational design and synthesis of a modified, unsymmetrical "first-generation" catalyst, which, in contrast to either first- or second-generation systems with symmetrical ligands, converts a mixture of two cycloolefin monomers to a largely alternating copolymer. The mechanistic concept of a homogeneous catalyst that switches between more than one state at each turnover is general. The structures of the complexes, determined by mass spectrometry, NMR, and X-ray crystallography, reveal some unexpected features, which explain sequence errors in the copolymer.