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Developing donors for Ziegler‐Natta (ZN) catalysis to control the polymerization reaction and produce polymers with desirable properties has always been challenging due to the multi‐component nature of the catalytic systems. Here, we have developed a new synthetic protocol for making two external donors, D1 (2,2,2‐trifluoroethyl myristate) and D2 (2,2,2‐trifluoroethyl palmitate) that show self‐extinguishing properties, followed by a systematic DFT study to understand this peculiar property of these donors. D1 and D2 can undergo parallel reactions with aluminum and titanium species present in the system to produce ketones and aldehydes, which are poisons for ZN catalytic systems, thus explaining their self‐extinguishing nature. The non‐covalent interaction between the long alkyl chain of the donors with the surface plays a vital role in determining the donors′ self‐extinguishing nature. There is a significant thermodynamic preference for the binding of the donor with the longer alkyl chain at the titanium center. The current work, therefore, provides interesting insights into how self‐extinguishing donors function in ZN catalytic systems. [ABSTRACT FROM AUTHOR]

The development of new donors (Lewisbases, usually containingoxygen atoms) is one of the chief areas of research in Ziegler–Natta(ZN) olefin polymerization systems. The addition of such donors hasled to improvement in the activity and selectivity of ZN systems.However, in order for the donor to be effective, it has to be chemicallystable and resistant to decomposition by Lewis acidic species suchas AlEt3. Discussed in the current work is the chemicalstability of different ester donors, including aromatic benzoate donorsand the silyl estera promising new donor class in ZN systems.Full quantum chemical calculations with density functional theory(DFT) indicate that esters can undergo decomposition through differentpathways upon interaction with species such as the AlEt3dimer: Al2Et6. Moreover, the studies showthat the active, supported titanium catalyst species can cause donordecomposition and, in fact, is likely to be the greater threat todonor decomposition than Al2Et6. This explainswhy the addition of excess donors can lead to the poisoning of theactive site in ZN systems. We have also computationally investigatedmeans of improving the silyl ester donors in order to make them morerobust and resilient to donor decomposition by Al2Et6and the supported active titanium species. [ABSTRACT FROM AUTHOR]