Obuah, CollinsJordaan, Johan H.L.Otto, Daniel P.Lochee, YemanlallZinyemba, Orpah2016-09-062016-09-062015Obuah, C. et al. 2015. (Ferrocenylpyrazolyl)zinc(II) acetate complexes as initiators and catalysts for the ring opening polymerization of ϵ-caprolacton. Journal of molecular catalysis A, 406:185-193. [https://doi.org/10.1016/j.molcata.2015.05.021]1381-11691873-314X (Online)http://hdl.handle.net/10394/18553https://doi.org/10.1016/j.molcata.2015.05.021https://www.sciencedirect.com/science/article/pii/S1381116915002058The reaction of Zn(OAc)2 with 3-ferrocenylpyrazol-1-ylmethylenepyridine (L1), 3-ferrocenyl-5-methylpyrazol-1-ylmethylenepyridine (L2), 3-ferrocenylpyrazol-1-ylethylamine (L3) and 3-ferrocenyl-5-pyrazol-1-ylethylamine (L4) afford the corresponding zinc complexes [Zn(CH3COO)2(L1)] (1), [Zn(CH3COO)2(L2)] (2), [Zn(CH3COO)2(L3)] (3), and [Zn(CH3COO)2(L4)] (4). These zinc complexes behave as catalysts or initiators for the ring opening polymerization of ϵ-caprolactone, depending on the nature of the ligands, to produce polymers that are capped with α,ω-dihydroxy, hydroxyl or ferrocenylpyrazolylethylamino end groups. Complexes 1 and 2 were found to act as catalysts when the [CL]/[C] ratios were varied from 100 to 800 to produce PCL with α,ω-dihydroxy and nearly the same molecular weight. Complexes 3 and 4 on the other hand act as initiators to produce a mixture of PCL that have polymers with ferrocenylpyrazolylethylamino and a hydroxyl as end groups as the major component of the mixture and minor species with α,ω-dihydroxy end groupen(Ferrocenylpyrazolyl)zinc(II) acetateϵ-caprolactoneRing opening polymerizationCatalystsInitiatorsArticle