ИСТИНА

Silicon-bridged C2-symmetric bis-indenyl ansa-metallocenes, so-called Spaleck-type catalysts, discovered in early 90s are one of the most extensively studied families of isospecific propylene polymerization catalysts. The most recent efforts resulted in development of catalysts with isoselectivity approaching that of Ziegler-Natta catalysts and ability to produce high-molecular weight polypropylene at high temperatures. However, despite that tens of C2-symmetric metallocenes have been synthesized and tested in olefin polymerization, there is still a lack of a comprehensive QSAR model across all the variety of catalysts of this type, which is mostly due to the difference in the polymerization conditions used by different groups in academia and industry, and of course in the objectives of their studies. This project, which is a part of collaboration with the University of Naples Federico II, is aimed at QSAR-modeling of polymerization behavior of variously substituted Spaleck catalysts. In this way, synthesis of a total of 42 Spaleck-type metallocenes was performed including a parallel strategy based on Negishi cross-coupling of the bromo-substituted parent metallocenes, as well as conventional synthetic methods.