TY - JOUR
T1 - (Ferrocenylpyrazolyl)zinc(II) acetate complexes as initiators and catalysts for the ring opening polymerization of ∈ -caprolacton
AU - Obuah, Collins
AU - Lochee, Yemanlall
AU - Zinyemba, Orpah
AU - Jordaan, Johan H.L.
AU - Otto, Daniel P.
AU - Darkwa, James
N1 - Publisher Copyright:
© 2015 Elsevier B.V. All rights reserved.
PY - 2015/6/19
Y1 - 2015/6/19
N2 - The 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 ∈ -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 group.
AB - The 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 ∈ -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 group.
KW - Catalysts
KW - Ferrocenylpyrazolyl zinc(II) acetate
KW - Initiators
KW - Ring opening polymerization
KW - ∈ -Caprolactone
UR - http://www.scopus.com/inward/record.url?scp=84935891763&partnerID=8YFLogxK
U2 - 10.1016/j.molcata.2015.05.021
DO - 10.1016/j.molcata.2015.05.021
M3 - Article
AN - SCOPUS:84935891763
SN - 1381-1169
VL - 406
SP - 185
EP - 193
JO - Journal of Molecular Catalysis A: Chemical
JF - Journal of Molecular Catalysis A: Chemical
ER -