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Barrera-Nava MP, Navarro R, Marcos-Fernández Á, Báez JE. Synthesis and characterization of macrodiols and non-segmented poly(ester-urethanes) (PEUs) derived from α,ω-hydroxy telechelic poly(ε-caprolactone) (HOPCLOH): effect of initiator, degree of polymerization, and diisocyanate. RSC Adv 2024; 14:27241-27251. [PMID: 39193304 PMCID: PMC11348852 DOI: 10.1039/d4ra03951c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2024] [Accepted: 08/19/2024] [Indexed: 08/29/2024] Open
Abstract
Nine different macrodiols derived from α,ω-hydroxy telechelic poly(ε-caprolactone) (HOPCLOH) were prepared by ring-opening polymerization of ε-caprolactone (CL) using three linear aliphatic diols (HO-(CH2) n -OH, where n = 4, 8, and 12) as initiators and catalyzed by ammonium decamolybdate (NH4)8[Mo10O34]. The crystallization temperature (T c) and crystallinity (x i) were relatively high for HOPCLOH species with a long aliphatic chain [-(CH2)12-] in the oligoester. Also, HOPCLOH was the precursor of twenty-seven different poly(ester-urethanes) (PEUs) with various degrees of polymerization (DP) of HOPCLOH and three types of diisocyanates such as 1,6-hexamethylene diisocyanate (HDI), methylene diphenyl diisocyanate (MDI), and 4,4'-methylenebis (cyclohexyl isocyanate) (HMDI). HOPCLOH exhibited the melting temperature (T m) and crystallinity (x i) with a proportional dependency to the degree of polymerization (DP). PEUs showed significant thermal and mechanical properties, which had a direct correlation in terms of the type of DP and diisocyanate. PEUs derived from HDI versus MDI or HMDI exhibited an apparent effect where aliphatic diisocyanate (HDI) induced a significant x i with respect to aromatic and cyclic diisocyanate (MDI or HMDI). The profile of PEUs films according to mechanical properties is mainly a plastic behavior. The chemical nature and properties of HOPCLOH and PEUs were characterized by NMR, FT-IR, GPC, MALDI-TOF, DSC, and mechanical properties.
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Affiliation(s)
- Miriam P Barrera-Nava
- Department of Chemistry, University of Guanajuato (UG) Noria Alta S/N 36050 Guanajuato Gto Mexico
| | - Rodrigo Navarro
- Institute of Polymer Science and Technology, CSIC C/Juan de la Cierva No. 3 28006 Madrid Spain
| | - Ángel Marcos-Fernández
- Institute of Polymer Science and Technology, CSIC C/Juan de la Cierva No. 3 28006 Madrid Spain
| | - José E Báez
- Department of Chemistry, University of Guanajuato (UG) Noria Alta S/N 36050 Guanajuato Gto Mexico
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2
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Akintayo DC, Munzeiwa WA, Jonnalagadda SB, Omondi B. Ring-opening polymerization of lactides and ε-caprolactone catalyzed by Zn(II) aryl carboxylate complexes supported by 4-pyridinyl schiff base ligands. Heliyon 2023; 9:e13514. [PMID: 36846710 PMCID: PMC9950825 DOI: 10.1016/j.heliyon.2023.e13514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/26/2023] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
Synthesis and catalytic studies of aryl carboxylate Zn (II) complexes is reported. Reaction of substituted (E)-N-phenyl-1-(pyridin-4-yl)methanimine with a methanolic solution of Zn(CH3COO)2 and substituted aryl carboxylate co-ligands gave heteroleptic Zn(II) complexes; [Zn(C6H5COO)2(L1)]2 (1), [Zn(C7H7COO)2(L1)]2 (2), [Zn (4-F-C6H4COO)2(L1)]2 (3), [Zn(C6H5COO)2(L2)]2 (4), [Zn(C7H7COO)2(L2)]2 (5), [Zn (4-F-C6H4COO)2(L2)]2 (6), [Zn(C6H5COO)2(L3)]2 (7), [Zn(C7H7COO)2(L3)]2 (8), [Zn (4-F-C6H4COO)2(L3)]2 (9). The molecular structures of complexes 1 and 4 are dinuclear with the zinc atom in complex 1 adopting a distorted trigonal bipyramidal geometry in a bi-metallacycle while complex 4 is square pyramidal where all four benzoate ligands bridge the zinc metals in a paddle wheel arrangement. All complexes successfully initiated mass/bulk ring-opening polymerization (ROP) of ϵ-caprolactone (ϵ-CL) and lactides (LAs) monomers with or without alcohol co-initiators at elevated temperatures. Complexes 1, 4 and 6 containing the unsubstituted benzoate co-ligands were the most active in their triad; with complex 4 being the most active (k app) of 0.3450 h-1. The physicochemical properties of the polymerization products of l-lactide and rac-lactide in toluene revealed melting temperatures (Tm) between 116.58 °C and 188.03 °C, and decomposition temperatures between 278.78 °C and 331.32 °C suggestive of an isotactic PLA with a metal capped end.
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Affiliation(s)
- Damilola C. Akintayo
- School of Chemistry & Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
| | - Wisdom A. Munzeiwa
- School of Chemistry & Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
- Chemistry Department, Bindura University of Science Education, Private Bag 1020, Bindura, Zimbabwe
| | - Sreekantha B. Jonnalagadda
- School of Chemistry & Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
| | - Bernard Omondi
- School of Chemistry & Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban, 4000, South Africa
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N3/4-pyridinyl Schiff base copper(II) benzoate complexes: synthesis, crystal structures and ring-opening polymerization studies. TRANSIT METAL CHEM 2022. [DOI: 10.1007/s11243-022-00494-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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4
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Zn(II) pyridinyl amine complexes, synthesis and crystal structure studies: A comparative study of the effect of nuclearity and benzoate type on the ring-opening polymerization of cyclic esters. Polyhedron 2022. [DOI: 10.1016/j.poly.2021.115589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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5
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Akintayo DC, Munzeiwa WA, Jonnalagadda SB, Omondi B. Ring-opening polymerization of cyclic esters by 3- and 4-pyridinyl Schiff base Zn(II) and Cu(II) paddlewheel complexes: kinetic, mechanistic and tacticity studies. ARAB J CHEM 2021. [DOI: 10.1016/j.arabjc.2021.103313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Appavoo D, Spencer LC, Guzei IA, Gómez-García CJ, van Wyk JL, Darkwa J. Ring opening polymerization of d,l-lactide and ε-caprolactone catalysed by (pyrazol-1-yl)copper(ii) carboxylate complexes. RSC Adv 2021; 11:13475-13485. [PMID: 35423870 PMCID: PMC8697578 DOI: 10.1039/d1ra00339a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 03/24/2021] [Indexed: 01/24/2023] Open
Abstract
1,2-Bis{(3,5-dimethylpyrazol-1-yl)methyl}benzene (L) reacts with [Cu(OAc)2] and C6H5COOH, 4-OH-C6H4COOH, 2-Cl-C6H4COOH and (3,5-NO2)2-C6H3COOH to afford the copper complexes [Cu2(C6H5COO)4(L)2] (1), [Cu2(4-OH-C6H4COO)4(L)2] (2), [Cu2(2-Cl-C6H4COO)4(L)2]n (3) and [Cu{(3,5-NO2)2-C6H3COO}2L]n (4) which are characterised by IR, mass spectrometry, elemental analyses, and X-ray crystallography. The structural data revealed two geometries that are adopted by the complexes: (i) paddle wheel in 1, 2·7H2O, 3 and (ii) regular chains in 3 and 4. Magnetic studies show strong antiferromagnetic couplings in the paddle wheel complexes and a weak antiferromagnetic coupling in the monometallic chain one. Catalysis studies performed with these complexes (1–4) showed that they initiate ring opening polymerization (ROP) of ε-caprolactone (ε-CL) under solvent-free conditions and d,l-lactide in toluene at elevated temperatures. Polycaprolactone (PCL) and poly(d,l-lactide) (PLA) obtained from the polymerization reactions are of low molecular weights (858 for PCL and 602 Da for PLA for initiator 1) and polydispersity indices (typically 2.16 for PCL and 1.64 for PLA with 1 as the initiator). End group analysis of the polymers, determined by MALDI-ToF MS, indicates that the polymers have benzoate, hydroxyl, methoxy and cyclic end groups. We report the synthesis, structure and complete characterization of four new pyrazolyl carboxylate-based copper(ii) complexes that catalyze the ring opening polymerization of ε-caprolactone under solvent-free conditions and of d,l-lactide in toluene.![]()
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Affiliation(s)
- Divambal Appavoo
- Department of Chemical Sciences, University of Johannesburg P.O. Box X524, Auckland Park, 2006 South Africa
| | - Lara C Spencer
- Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
| | - Ilia A Guzei
- Department of Chemical Sciences, University of Johannesburg P.O. Box X524, Auckland Park, 2006 South Africa .,Department of Chemistry, University of Wisconsin-Madison Madison WI 53706 USA
| | - Carlos J Gómez-García
- Department of Inorganic Chemistry and ICMol, C/ Catedrático José Beltrán, 2. University of Valencia 46980 Paterna Valencia Spain
| | - Juanita L van Wyk
- Department of Chemical Sciences, University of Johannesburg P.O. Box X524, Auckland Park, 2006 South Africa
| | - James Darkwa
- Department of Chemical Sciences, University of Johannesburg P.O. Box X524, Auckland Park, 2006 South Africa
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Choe S, Lee H, Nayab S. Diverse coordination geometry of cobalt (II), zinc (II), and cadmium (II) complexes comprising
N
,
N
‐bis(1H‐pyrazol‐1‐yl)methyl)amines derivatives: Synthesis, structures, and ring opening polymerization of
rac
‐lactide. Appl Organomet Chem 2021. [DOI: 10.1002/aoc.6204] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Solhye Choe
- Department of Chemistry and Green‐Nano Materials Research Center Kyungpook National University Daegu South Korea
| | - Hyosun Lee
- Department of Chemistry and Green‐Nano Materials Research Center Kyungpook National University Daegu South Korea
| | - Saira Nayab
- Department of Chemistry Shaheed Benazir Bhutto University Sheringal Dir (U) Pakistan
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Alshamrani AFA, Santoro O, Ounsworth S, Prior TJ, Stasiuk GJ, Redshaw C. Synthesis, characterisation and ROP catalytic evaluation of Cu(II) complexes bearing 2,2ʹ-diphenylglycine-derived moieties. Polyhedron 2021. [DOI: 10.1016/j.poly.2020.114977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Choe S, Lee H, Nayab S. Synthesis, structures, and catalytic efficiency in ring opening polymerization of rac-lactide with tridentate vs. bidentate cobalt( ii), zinc( ii), and cadmium( ii) complexes containing N-substituted N, N-bis((3,5-dimethyl-1 H-pyrazol-1-yl)methyl)amine ligands. RSC Adv 2021; 11:18840-18851. [PMID: 35478641 PMCID: PMC9033469 DOI: 10.1039/d1ra02365a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/20/2021] [Indexed: 01/09/2023] Open
Abstract
A series of Co(ii), Zn(ii), and Cd(ii) complexes supported by 1-(3,5-dimethyl-1H-pyrazol-1-yl)-N-((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-N-(furan-2-ylmethyl)methanamine (LA) and N,N-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)-4-isopropylaniline (LB) were synthesized. The direct chelation of CoCl2·6H2O, ZnCl2, and CdBr2·4H2O by the ligands produced [LnMX2] (Ln = LA or LB; M = Zn or Co, with X = Cl; M = Cd, with X = Br) complexes in high yields. Structural studies revealed that [LBCoCl2] and [LBZnCl2] adopted distorted tetrahedral geometries, as LB coordinated the metal centers in a bidentate fashion, while LA coordinated the metal centers in a tridentate fashion through the nitrogen atoms of the pyrazole and amine moieties, so that [LACoCl2] and [LAZnCl2] exhibited trigonal bipyramidal geometries and [LACdBr2] a square pyramidal geometry. [LBCdBr2] has two Cd-containing structures per unit cell, whereby one Cd center adopted a distorted tetrahedral geometry and the other exhibited square bipyramidal geometry. The in situ-generated alkyl derivatives of the synthesized complexes were assessed in the ring-opening polymerization of rac-lactide. Heterotactic polylactides (PLAs) were furnished with all complexes. The [LBZnCl2]/MeLi system produced PLA with a superior heterotactic bias (Pr up to 0.94) at −25 °C. PLAs with wide-ranging polydispersity indices (1.16–2.23) and low molecular weights were produced in all cases, irrespective of the specific M(II) center and ancillary ligand utilized. Co(ii), Zn(ii), and Cd(ii) complexes supported by bis-pyrazolyl ligands were applied to the ring-opening polymerization of rac-lactide to produce heterotactic polylactides (PLAs) with superior heterotactic bias i.e. Pr up to 0.94 at −25 °C.![]()
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Affiliation(s)
- Solhye Choe
- Department of Chemistry and Green-Nano Materials Research Center
- Kyungpook National University
- Daegu
- Republic of Korea
| | - Hyosun Lee
- Department of Chemistry and Green-Nano Materials Research Center
- Kyungpook National University
- Daegu
- Republic of Korea
| | - Saira Nayab
- Department of Chemistry
- Shaheed Benazir Bhutto University
- Islamic Republic of Pakistan
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Nikovsky IA, Polezhaev AV, Melnikova EK, Nelyubina Y. New Iron(III) Oxo Complex with Substituted 2,6-Bis(Pyrazol-3-yl)Pyridine. RUSS J INORG CHEM+ 2020. [DOI: 10.1134/s0036023620060145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Nikovskii IA, Polezhaev AV, Aleshin DY, Mel’nikova EK, Dorovatovskii PV, Nelyubina YV. Iron(II) and Cobalt(II) Complexes with 2,6-Bis(1,4-Diphenyl-5-Hydroxy-1H-Pyrazol-3-yl)pyridine: Synthesis, Structures, and Spin States. RUSS J COORD CHEM+ 2020. [DOI: 10.1134/s1070328420050048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Munzeiwa WA, Nyamori VO, Omondi B. N,O-Amino-phenolate Mg(II) and Zn(II) Schiff base complexes: Synthesis and application in ring-opening polymerization of ε-caprolactone and lactides. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.12.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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13
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Polymers of ε-Caprolactone Using New Copper(II) and Zinc(II) Complexes as Initiators: Synthesis, Characterization and X-Ray Crystal Structures. Polymers (Basel) 2018; 10:polym10111239. [PMID: 30961164 PMCID: PMC6401771 DOI: 10.3390/polym10111239] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Revised: 11/02/2018] [Accepted: 11/05/2018] [Indexed: 11/17/2022] Open
Abstract
Five of six new Zn(II) and Cu(II) complexes were active in the ring-opening polymerization (ROP) of ε-caprolactone (CL) under solvent-free conditions, producing polycaprolactones (PCLs) of high crystallinity with molecular weights between 22,900 and 38,700 g mol−1 and decomposition temperatures above 260 °C. 1H NMR analysis demonstrated that the PCLs obtained were mainly linear, having hydroxymethylene groups at the chain ends. The results obtained indicated a significant improvement in terms of the ratio of monomer:initiator compared to related Cu(II) and Zn(II) complexes. In addition, the structures of the complexes 1 and 4 were determined by single-crystal X-ray diffraction. The synthesis and full characterization of all complexes are described in this paper.
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El-Massaoudi M, Radi S, Mabkhot YN, Al–Showiman SS, Ghabbour HA, Ferbinteanu M, Adarsh N, Garcia Y. Cu(II) and Mn(II) coordination complexes constructed by C linked bispyrazoles: Effect of anions and hydrogen bonding on the self assembly process. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.06.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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15
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Munzeiwa WA, Nyamori VO, Omondi B. Zn(II) and Cu(II) unsymmetrical formamidine complexes as effective initiators for ring-opening polymerization of cyclic esters. Appl Organomet Chem 2018. [DOI: 10.1002/aoc.4247] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Wisdom A. Munzeiwa
- School of Chemistry and Physics; University of KwaZulu-Natal; Westville Campus, Private Bag X54001 Durban 4000 South Africa
| | - Vincent O. Nyamori
- School of Chemistry and Physics; University of KwaZulu-Natal; Westville Campus, Private Bag X54001 Durban 4000 South Africa
| | - Bernard Omondi
- School of Chemistry and Physics; University of KwaZulu-Natal; Westville Campus, Private Bag X54001 Durban 4000 South Africa
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16
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Munzeiwa WA, Omondi B, Nyamori VO. Synthesis and polymerization kinetics of ε-caprolactone and ʟ-lactide to low molecular weight polyesters catalyzed by Zn(II) and Cu(II) N -hydroxy- N , N ′-diarylformamidine complexes. Polyhedron 2017. [DOI: 10.1016/j.poly.2017.09.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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17
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Rueda-Espinosa J, Torres JF, Gauthier CV, Wojtas L, Verma G, Macías MA, Hurtado J. Copper(II) Complexes with Tridentate Bis(pyrazolylmethyl)pyridine Ligands: Synthesis, X-ray Crystal Structures and ϵ-Caprolactone Polymerization. ChemistrySelect 2017. [DOI: 10.1002/slct.201701820] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Juan Rueda-Espinosa
- Department of Chemistry; Universidad de los Andes; Carrera 1 N° 18 A-12 111711 Bogotá Colombia
| | - Juan F. Torres
- Department of Chemistry; Universidad de los Andes; Carrera 1 N° 18 A-12 111711 Bogotá Colombia
| | - Carmen Valdez Gauthier
- Department of Chemistry, Biochemistry and Physics; Florida Southern College; 111 Lake Hollingsworth Drive Lakeland, FL 33801 USA
| | - Lukasz Wojtas
- Department of Chemistry; University of South Florida; 4202 East Fowler Ave. Tampa, FL 33620 USA
| | - Gaurav Verma
- Department of Chemistry; University of South Florida; 4202 East Fowler Ave. Tampa, FL 33620 USA
| | - Mario A. Macías
- Department of Chemistry; Universidad de los Andes; Carrera 1 N° 18 A-12 111711 Bogotá Colombia
| | - John Hurtado
- Department of Chemistry; Universidad de los Andes; Carrera 1 N° 18 A-12 111711 Bogotá Colombia
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Njogu EM, Omondi B, Nyamori VO. Silver(I)-pyridinyl Schiff base complexes: Synthesis, structural characterization and reactivity in ring-opening polymerisation of ε-caprolactone. Inorganica Chim Acta 2017. [DOI: 10.1016/j.ica.2016.12.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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19
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Zikode M, Ojwach SO, Akerman MP. Structurally rigid bis(pyrazolyl)pyridine Zn(II) and Cu(II) complexes: Structures and kinetic studies in ring-opening polymerization of ε-caprolactone. Appl Organomet Chem 2016. [DOI: 10.1002/aoc.3556] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Mnqobi Zikode
- School of Chemistry & Physics; University of KwaZulu-Natal; Pietermaritzburg Campus, Private Bag X01 Scottsville 3209 South Africa
| | - Stephen O. Ojwach
- School of Chemistry & Physics; University of KwaZulu-Natal; Pietermaritzburg Campus, Private Bag X01 Scottsville 3209 South Africa
| | - Matthew P. Akerman
- School of Chemistry & Physics; University of KwaZulu-Natal; Pietermaritzburg Campus, Private Bag X01 Scottsville 3209 South Africa
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