1
|
Chen ZH, Daugulis O, Brookhart M. Polymerization of Terminal Acetylenes by a Bulky Monophosphine-Palladium Catalyst. Organometallics 2023. [DOI: 10.1021/acs.organomet.2c00561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Zhi-Hao Chen
- Center for Polymer Chemistry, Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
| | - Olafs Daugulis
- Center for Polymer Chemistry, Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
| | - Maurice Brookhart
- Center for Polymer Chemistry, Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
| |
Collapse
|
2
|
Controlling the reactivity of [Pd (II)(N^N^N)Cl] + complexes using 2,6-bis(pyrazol-2-yl)pyridine ligands for biological application: Substitution reactivity, CT-DNA interactions and in vitro cytotoxicity study. J Inorg Biochem 2020; 213:111261. [PMID: 33011625 DOI: 10.1016/j.jinorgbio.2020.111261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 09/09/2020] [Accepted: 09/21/2020] [Indexed: 12/24/2022]
Abstract
Four [(N^N^N)Pd(II)Cl]+ complexes [chloride-(2,2':6',2''-terpyridine)Pd(II)]Cl (PdL1), [chlorido(2,6-bis(N-pyrazol-2-yl)pyridine)Pd(II)]Cl (PdL2), [chlorido(2,6-bis(3,5-dimethyl-N-pyrazol-2-yl)pyridine)Pd(II)]Cl (PdL3) and [chlorido(2,6-bis(3,5-dimethyl-N-pyrazol-2-ylmethyl)pyridine)Pd(II)]BF4 (PdL4) were synthesized and characterized. The rates of substitution of these Pd(II) complexes with thiourea nucleophiles viz; thiourea (Tu), N,N'-dimethylthiourea (Dmtu) and N,N,N',N'-tetramethylthiourea (Tmtu) was investigated under pseudo first-order conditions as a function of nucleophile concentration [Nu] and temperature using the stopped-flow technique. The observed rate constants vary linearly with [Nu]; kobs = k2[Nu] and decreased in the order: PdL1 > PdL2 > PdL3 ≫ PdL4. The lower π-acceptability of the cis-coordinated N-pyrazol-2-yl groups (which coordinates via pyrazollic-N π-donor atoms) of the PdL2-4 significantly decelerates the reactivity relative to PdL1. Furthermore, the six-membered chelates having methylene bridge in PdL4 do not allow π-extension in the ligand and introduces steric hindrance further lowering the reactivity. Trends in DFT calculated data supported the observed reactivity trend. Spectrophotometric titration data of complexes with calf thymus DNA (CT-DNA) and viscosity measurements of the resultant mixtures suggested that associative interactions occur between the complexes and CT-DNA, likely through groove binding with high binding constants (Kb = 104 M-1). In vitro MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] cytotoxic activity data showed that PdL1 was the most potent complex against MCF7 breast cancer cells; its IC50 value is lower than that of cisplatin. The results demonstrate how modification of a spectator ligand can be used to slow down the reactivity of Pd(II) complexes. This is of special importance in controlling drug toxicity in both pharmaceutical and biomedical applications.
Collapse
|
3
|
Omondi RO, Bellam R, Ojwach SO, Jaganyi D, Fatokun AA. Palladium(II) complexes of tridentate bis(benzazole) ligands: Structural, substitution kinetics, DNA interactions and cytotoxicity studies. J Inorg Biochem 2020; 210:111156. [DOI: 10.1016/j.jinorgbio.2020.111156] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2020] [Revised: 06/15/2020] [Accepted: 06/21/2020] [Indexed: 01/21/2023]
|
4
|
Atakol A, Svoboda I, Dal H, Atakol O, Nazır H. New energetic Silver(I) complexes with Nnn type Pyrazolylpyridine ligands and oxidizing anions. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
5
|
Das S, Subramaniyan V, Mani G. Nickel(II) and Palladium(II) Complexes Bearing an Unsymmetrical Pyrrole-Based PNN Pincer and Their Norbornene Polymerization Behaviors versus the Symmetrical NNN and PNP Pincers. Inorg Chem 2019; 58:3444-3456. [PMID: 30767515 DOI: 10.1021/acs.inorgchem.8b03562] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Unsymmetrical pincers have been shown to be better than the corresponding symmetrical pincers in several catalysis reactions. A new unsymmetrical PNN propincer, 2-(3,5-dimethylpyrazolylmethyl)-5-(diphenylphosphinomethyl)pyrrole (1), was synthesized from pyrrole through Mannich bases in a good yield. In addition, the new byproduct 2-(3,5-dimethylpyrazolylmethyl)-5-(dimethylaminomethyl)- N-(hydroxymethyl)pyrrole was also isolated. The reaction of 1 with [PdCl2(PhCN)2] and Et3N in toluene yielded [PdCl{C4H2N-2-(CH2Me2pz)-5-(CH2PPh2)-κ3 P,N,N}] (2). The analogous reaction between 1 and [NiCl2(DME)] or NiX2 (X = Br, I) in the presence of NEt3 in acetonitrile afforded [NiX{C4H2N-2-(CH2Me2pz)-5-(CH2PPh2)-κ3 P,N,N}] (3; X = Cl, Br, I). All complexes were structurally characterized. The norbornene polymerization behaviors of the unsymmetrical pincer complexes 2 and 3 in the presence of MMAO or EtAlCl2 were compared with those of the symmetrical pincer complexes chloro[2,5-bis(3,5-dimethylpyrazolylmethyl)pyrrolido]palladium(II) (NNN), chloro[2,5-bis(diphenylphosphinomethyl)pyrrolido]palladium(II), and chloro[2,5-bis(diphenylphosphinomethyl)pyrrolido]nickel(II) (PNP) at different temperatures. The PNN and NNN complexes exhibited far greater activity on the order of 107 g of PNB/mol/h, with quantitative yields in some cases, in comparison to the PNP pincer palladium and nickel complexes. This trend was also supported by the iPr group substituted PNP nickel and palladium pincer complexes. These polymerization behaviors are explained using steric crowding around the metal atom with the support of NMR studies and suggested that the activity increases as the Npyrazole donor increases. Polymers were characterized by 1H NMR, IR, TGA, and powder XRD methods.
Collapse
Affiliation(s)
- Sanghamitra Das
- Department of Chemistry , Indian Institute of Technology Kharagpur , Kharagpur , West Bengal , India 721 302
| | - Vasudevan Subramaniyan
- Department of Chemistry , Indian Institute of Technology Kharagpur , Kharagpur , West Bengal , India 721 302
| | - Ganesan Mani
- Department of Chemistry , Indian Institute of Technology Kharagpur , Kharagpur , West Bengal , India 721 302
| |
Collapse
|
6
|
Dikmen G, Hür D. Palladium (II) complex: Synthesis, spectroscopic studies and DFT calculations. Chem Phys Lett 2019. [DOI: 10.1016/j.cplett.2018.12.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
7
|
Joseph MC, Swarts AJ, Mapolie SF. Phenylacetylene polymerisation mediated by cationic cyclometallated palladium(ii) complexes bearing benzylidene 2,6-diisopropylphenylamine and its derivatives as ligands. Dalton Trans 2018; 47:12209-12217. [PMID: 30046800 DOI: 10.1039/c8dt02728e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of novel cationic palladacycle complexes bearing benzylidene-2,6-diisopropylphenylamine derivatives as ligands and with the general formula [Pd(MeCN)(L)(R-C6H3)CH[double bond, length as m-dash]N{2,6-iPr2-C6H3}][B(3,5-(CF3)2-C6H3)] (R = H, Cl, Br, F, OMe and L = 1,3,5-triaza-7-phosphaadamantane (PTA), tricyclohexylphosphine (PCy3) and triphenylphosphine (PPh3)) were prepared and characterized by a range of analytical techniques. These cationic palladacycle complexes were found to be active precatalysts for the polymerisation of phenylacetylene. The meta-substituent on the cyclometallated ring was found to have a marked effect on the catalyst performance in that complexes, which contained electron-withdrawing substituents, were found to be the most active in the polymerisation process. Furthermore, increasing the steric bulk of the phosphine ligand led to the production of higher molecular weight polyphenylacetylenes (PPA). Polymerisation reactions performed at 25 °C gave a mixture of both cis-transoidal and trans-cisoidal PPA while trans-cisoidal PPA was selectively produced at elevated temperatures (60 °C). Preliminary mechanistic studies demonstrated that polymerisation proceeds via dissociation of the C,N-chelating ligand, and involves the formation of an iminium cationic fragment.
Collapse
Affiliation(s)
- M Cassiem Joseph
- DST-NRF Centre of Excellence in Catalysis (c*change), Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag 1, Matieland, 7601 Stellenbosch, South Africa.
| | | | | |
Collapse
|
8
|
Wu X, Yang Z, Yan X, Zhang P, Wang L, Guo G, Dong Y, Li X. Polymerization of 1-chloro-2-phenylacetylene by cationic monoanionic tridentate ( S, S)-bis(oxazolinylphenyl)amido-ligated palladium catalysts: is it a coordination–insertion mechanism? Polym Chem 2018. [DOI: 10.1039/c8py00903a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Cationic (S,S)-bis(oxazolinylphenyl)amido-ligated palladium species were first used for the coordination–insertion polymerization of 1-chloro-2-phenylacetylenes.
Collapse
Affiliation(s)
- Xiaolu Wu
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing
- China
| | - Zhi Yang
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing
- China
| | - Xinwen Yan
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing
- China
| | - Pengfei Zhang
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing
- China
| | - Lin Wang
- School of Mechatronical Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
| | - Ge Guo
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing
- China
| | - Yuping Dong
- Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications
- School of Materials Science and Engineering
- Beijing Institute of Technology
- Beijing 100081
- China
| | - Xiaofang Li
- Key Laboratory of Cluster Science of Ministry of Education
- School of Chemistry and Chemical Engineering
- Beijing Institute of Technology
- Beijing
- China
| |
Collapse
|
9
|
Wang Y, Wang W, Wang X, Cheng X, Qin A, Sun JZ, Tang BZ. Polymerization of 1-chloro-2-benzaldehyde-acetylene using an NHC-Pd/AgOTf catalyst and post-polymerization modification. Polym Chem 2017. [DOI: 10.1039/c7py01110e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Using NHC-Pd/AgOTf complex as catalyst, we realized the polymerization of 1-chloro-2-phenylacetylene derivative, which bears an electron-withdrawing aldehyde group for the subsequent post-polymerization modification.
Collapse
Affiliation(s)
- Yanmei Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Wenjie Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Xiao Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Xiao Cheng
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Anjun Qin
- Guangdong Innovative Research Team
- State Key Lab of Luminescent Materials and Devices
- South China University of Technology
- Guangzhou 510640
- China
| | - Jing Zhi Sun
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| | - Ben Zhong Tang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization
- Department of Polymer Science and Engineering
- Zhejiang University
- Hangzhou 310027
- China
| |
Collapse
|
10
|
Darkwa J. Palladium Catalyzed Phenylacetylene Polymerization to Low Molecular Weight cis-Transoidal and trans-Cisoidal Poly(phenylacetylene)s: A Perspective. POLYM REV 2016. [DOI: 10.1080/15583724.2016.1184165] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
11
|
Maroń A, Nycz JE, Machura B, Małecki JG. Luminescence properties of palladium(II) phenanthroline derivative coordination compounds. ChemistrySelect 2016. [DOI: 10.1002/slct.201600143] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Anna Maroń
- Department of Crystallography; Institute of Chemistry; University of Silesia; Szkolna 9 str. 40-006 Katowice Poland
| | - Jacek E. Nycz
- Institute of Chemistry; University of Silesia; Szkolna 9 str. 40-006 Katowice Poland
| | - Barbara Machura
- Department of Crystallography; Institute of Chemistry; University of Silesia; Szkolna 9 str. 40-006 Katowice Poland
| | - Jan G. Małecki
- Department of Crystallography; Institute of Chemistry; University of Silesia; Szkolna 9 str. 40-006 Katowice Poland
| |
Collapse
|
12
|
Białek MJ, Latos-Grażyński L. Palladium(II), Ruthenium(II), and Ruthenium(III) Complexes of 23-Thiaazuliporphyrin: The Case of Coordination-Induced Contraction. Inorg Chem 2016; 55:1758-69. [DOI: 10.1021/acs.inorgchem.5b02684] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michał J. Białek
- Department of Chemistry, University of Wrocław, F.
Joliot-Curie 14, 50-383 Wrocław, Poland
| | | |
Collapse
|
13
|
Ojwach SO, Ogweno AO, Akerman MP. (Pyridyl)benzoazole palladium(ii) complexes as homogeneous catalysts in hydrogenation of alkenes and alkynes. Catal Sci Technol 2016. [DOI: 10.1039/c5cy02204e] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Complexes 1–6 form “cocktail” catalysts in the hydrogenation and isomerization of alkenes and alkynes where the active species are homogeneous.
Collapse
Affiliation(s)
- Stephen O. Ojwach
- School of Chemistry and Physics
- University of KwaZulu-Natal
- Pietermaritzburg
- South Africa
| | - Aloice O. Ogweno
- School of Chemistry and Physics
- University of KwaZulu-Natal
- Pietermaritzburg
- South Africa
| | - Matthew P. Akerman
- School of Chemistry and Physics
- University of KwaZulu-Natal
- Pietermaritzburg
- South Africa
| |
Collapse
|
14
|
Synthesis and crystal structures of a series of (μ-thiophenolato)(μ-pyrazolato-N,N′) double bridged dipalladium(II) complexes and their application in Mizoroki–Heck reaction as highly efficient catalysts. Inorganica Chim Acta 2016. [DOI: 10.1016/j.ica.2015.10.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
15
|
|
16
|
Son KS, Woo JO, Kim D, Kang SK. Crystal structure of di-chlorido-{2,6-bis-[(3-phenyl-1H-pyrazol-1-yl)meth-yl]pyridine}cobalt(II). Acta Crystallogr E Crystallogr Commun 2015; 71:m75-6. [PMID: 26029409 PMCID: PMC4438808 DOI: 10.1107/s2056989015003862] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 02/24/2015] [Indexed: 11/10/2022]
Abstract
In the title complex, [CoCl2(C25H21N5)], the Co(II) atom is coordinated by two Cl atoms and two N atoms, provided by a tridentate pyrazolylpyridyl ligand, forming a slightly distorted tetra-hedral geometry [range of angles: 96.51 (10) (chelate ring) to 118.60 (9)°]. The dihedral angle between Cl/Co/Cl and N/Co/N planes is 86.83 (7)°. The chelate ring has the conformation of a distorted boat. The dihedral angle between pyridyl ring and the coordinated pyrazolyl ring is 56.16 (12)°. The uncoordinated pyrazolyl ring is almost perpendicular to the pyridyl ring with the dihedral angle of 87.49 (10)°. In the crystal packing, inter-molecular phenyl-C-H ⋯π(pyrid-yl) inter-actions generate dimeric aggregates. These are connected into a zigzag supra-molecular chain along the c-axis direction via π-π inter-actions [inter-centroid distance between pyridyl and phenyl rings = 3.664 (2) Å].
Collapse
Affiliation(s)
- Kyung-sun Son
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Jeong Oh Woo
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Daeyoung Kim
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Sung Kwon Kang
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| |
Collapse
|
17
|
Son KS, Woo JO, Kim D, Kang SK. Crystal structure of 2,6-bis-[(1H-pyrazol-1-yl)meth-yl]pyridine. Acta Crystallogr Sect E Struct Rep Online 2014; 70:o973. [PMID: 25309287 PMCID: PMC4186076 DOI: 10.1107/s1600536814017474] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 07/30/2014] [Indexed: 11/11/2022]
Abstract
In the title compound, C13H13N5, the planes of the pyrazolyl groups are nearly perpendicular to that of the central pyridine ring, making dihedral angles of 87.77 (8) and 85.73 (7)°. In the crystal, weak C—H⋯N hydrogen bonds link the molecules into layers extending parallel to (10-1).
Collapse
Affiliation(s)
- Kyung-Sun Son
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Jeong Oh Woo
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Daeyoung Kim
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| | - Sung Kwon Kang
- Department of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
| |
Collapse
|
18
|
Obuah C, Omondi B, Nozaki K, Darkwa J. Solvent and co-catalyst dependent pyrazolylpyridinamine and pyrazolylpyrroleamine nickel(II) catalyzed oligomerization and polymerization of ethylene. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.molcata.2013.10.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
19
|
Characterization of a PdII complex with (E)-8-hydroxyquinoline-2-carbaldehyde O-benzyl oxime. MENDELEEV COMMUNICATIONS 2014. [DOI: 10.1016/j.mencom.2013.12.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
20
|
Ojwach SO, Okemwa TT, Attandoh NW, Omondi B. Structural and kinetic studies of the polymerization reactions of ε-caprolactone catalyzed by (pyrazol-1-ylmethyl)pyridine Cu(II) and Zn(II) complexes. Dalton Trans 2013; 42:10735-45. [PMID: 23774962 DOI: 10.1039/c3dt51338f] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The structural and kinetic studies of polymerization reactions of ε-caprolactone (ε-CL) using (pyrazolylmethyl)pyridine Cu(II) and Zn(II) complexes as initiators is described. Reactions of 2-(3,5-dimethylpyrazol-1-ylmethyl)pyridine (L1) and 2-(3,5-diphenylpyrazol-1-ylmethyl)pyridine (L2) with Zn(Ac)2·2H2O or Cu(Ac)2·2H2O produced the corresponding complexes [Zn(Ac)2(L1)] (1), [Cu(Ac)2(L1)] (2), [Zn(Ac)2(L2)] (3) and [Cu2(Ac)4(L2)2] (4) respectively. Solid state structures of 1 and 4 confirmed that complexes 1 and 4 are monomeric and dimeric respectively and that L1 is bidentate in 1 while L2 is monodentate in 4. X-band EPR spectra of 2 and 4 revealed that complex 2 is monomeric both in solid and solution state, while the paddle-wheel structure of 4 is retained in solution. Complexes 1-4 formed active initiators in the ring opening polymerization of ε-CL. Zn(II) complexes 1 and 3 exhibited higher rate constants of 0.044 h(-1) and 0.096 h(-1) respectively compared to rate constants of 0.017 h(-1) and 0.031 h(-1) observed for the corresponding Cu(II) complexes 2 and 4 respectively at 110 °C. All the polymerization reactions follow pseudo first-order kinetic with respect to ε-CL monomer. Initiator 1 showed first-order dependency on the polymerization reactions and utilizes only one active site as the initiating group. The molecular weights of the polymers produced range from 1982 g mol(-1) to 14,568 g mol(-1) and exhibited relatively broad molecular weight distributions associated with transesterification reactions.
Collapse
Affiliation(s)
- Stephen O Ojwach
- School of Chemistry and Physics, University of KwaZulu-Natal, Pietermaritzburg Campus, Private Bag X01 Scottsville, 3209, South Africa.
| | | | | | | |
Collapse
|
21
|
Małecki J. Spectroscopic, structure, and DFT studies of cationic palladium(II) complexes with imidazole derivative ligands. J COORD CHEM 2013. [DOI: 10.1080/00958972.2013.784903] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- J.G. Małecki
- a Department of Crystallography , Institute of Chemistry, University of Silesia , Katowice , Poland
| |
Collapse
|
22
|
Motswainyana WM, Onani MO, Jacobs J, Van Meervelt L. Dichlorido{N-[2-(diphenylphosphanyl)benzylidene]-2-methylaniline}palladium(II) acetonitrile monosolvate. Acta Crystallogr C 2013; 69:209-11. [DOI: 10.1107/s0108270113002333] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 01/23/2013] [Indexed: 11/10/2022] Open
Abstract
The title imino–phosphine compound, [PdCl2(C26H22NP)]·CH3CN, was prepared by reaction ofN-[2-(diphenylphosphanyl)benzylidene]-2-methylaniline with dichlorido(cycloocta-1,5-diene)palladium(II) in dry CH2Cl2. The PdIIcation is coordinated by the P and N atoms of the bidentate chelating ligand and by two chloride anions, generating a distorted square-planar coordination geometry. There is a detectabletransinfluence for the chloride ligands. The methyl group present in this structure has an influence on the crystal packing.
Collapse
|
23
|
Małecki J, Maroń A. Characterization, molecular structures and fluorescent properties of Pd(II) and Ni(II) complexes with 1-benzyl-2-methylimidazole. Polyhedron 2013. [DOI: 10.1016/j.poly.2012.11.047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
24
|
Organometallic Complexes of Pyridines Together with Diverse Heterocycles as Ligands. ADVANCES IN HETEROCYCLIC CHEMISTRY 2013. [DOI: 10.1016/b978-0-12-407777-5.00002-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
|
25
|
McGowan KP, O'Reilly ME, Ghiviriga I, Abboud KA, Veige AS. Compelling mechanistic data and identification of the active species in tungsten-catalyzed alkyne polymerizations: conversion of a trianionic pincer into a new tetraanionic pincer-type ligand. Chem Sci 2013. [DOI: 10.1039/c2sc21750c] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
26
|
|
27
|
Motswainyana WM, Onani MO, Jacobs J, Van Meervelt L. Dichlorido{2-[(2,6-diethylphenyl)iminomethyl]quinoline-κ 2N, N′}palladium(II) acetonitrile monosolvate. Acta Crystallogr C 2012; 68:m356-8. [DOI: 10.1107/s0108270112045970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Accepted: 11/07/2012] [Indexed: 11/10/2022] Open
Abstract
The title complex, [PdCl2(C20H20N2)]·CH3CN, was synthesized by the reaction of 2-[(2,6-diethylphenyl)iminomethyl]quinoline with dichlorido(cycloocta-1,5-diene)palladium(II) in dry CH2Cl2. The PdIIion is coordinated by two N atoms of the bidentate quinoline ligand and by two chloride anions, generating a distorted square-planar coordination geometry around the metal centre. There is a detectabletransinfluence for the chloride ligands. The crystal packing is characterized by π–π stacking between the quinoline rings. The use of acetonitrile as the crystallization solvent was essential for obtaining good-quality crystals.
Collapse
|
28
|
Spencer LC, Guzei IA, Segapelo TV, Darkwa J. Dichlorido{2-[(3,5-diphenyl-1H-pyrazol-1-yl-κN2)methyl]pyridine-κN}palladium(II). Acta Crystallogr C 2012; 68:m317-9. [PMID: 23124452 DOI: 10.1107/s0108270112043119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 10/16/2012] [Indexed: 11/10/2022] Open
Abstract
The title compound, [PdCl(2)(C(21)H(17)N(3))], is a member of a sequence of Pd, Pt and Co dichloride complexes bearing polysubstituted (pyrazol-1-ylmethyl)pyridine ligands. It is shown that there is a correlation between the steric bulkiness of the bidentate (pyrazol-1-ylmethyl)pyridine ligands and the Pd-N(pyrazole) distances, i.e. the larger the ligand, the longer the bond. In contrast, no trend is observed between the steric properties of the ligand and the Pd-N(pyridine) bond lengths.
Collapse
Affiliation(s)
- Lara C Spencer
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA
| | | | | | | |
Collapse
|
29
|
Motswainyana WM, Onani MO. New phenylene bridged binuclear bis (imino-quinolyl) palladium (II) complexes: Synthesis, characterization and Heck reactions. INORG CHEM COMMUN 2012. [DOI: 10.1016/j.inoche.2012.07.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
30
|
Ojwach SO, Nyamato GS, Omondi B, Darkwa J. Chelating (pyrazolylmethyl)pyridine ligands: Coordination chemistry and binding properties with zinc(II) and cadmium(II) cations. Inorganica Chim Acta 2012. [DOI: 10.1016/j.ica.2012.07.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
31
|
Synthesis, characterization and molecular structure of Pd(II) complex containing the methyl-hemiacetal form of isonicotinaldehyde. Polyhedron 2012. [DOI: 10.1016/j.poly.2012.03.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
32
|
Guzei I, Herbst-Irmer R, Munyaneza A, Darkwa J. Detailed example of the identification and crystallographic analysis of a pseudo-merohedrally twinned crystal. ACTA CRYSTALLOGRAPHICA SECTION B: STRUCTURAL SCIENCE 2012; 68:150-7. [DOI: 10.1107/s0108768112002728] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 01/21/2012] [Indexed: 11/10/2022]
Abstract
A detailed description of the procedures utilized in the non-routine X-ray single-crystal structural determination and refinement of a pseudo-merohedrally twinned crystal of an Fe/Ni organometallic complex is presented. It illustrates to the practitioners of crystallography how to properly handle such cases and describes the logic and concrete steps necessary to account for the twinning, pseudo-symmetry and atomic positional disorder.
Collapse
|
33
|
Binuclear Pd-methyl complexes of N,N′-{1, n}-alkanediyl-bis(pyridinyl-2-methanimine) ligands (n = 5, 8, 9, 10 and 12): Evaluation as catalysts precursors for phenylacetylene polymerization. J Organomet Chem 2012. [DOI: 10.1016/j.jorganchem.2011.11.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
34
|
Ojwach SO, Nyamato GS, Omondi B, Darkwa J, Okoth AO. Multidentate bis(pyrazolylmethyl)pyridine ligands: coordination chemistry and binding properties with zinc(II) and cadmium(II) cations. J COORD CHEM 2012. [DOI: 10.1080/00958972.2011.651718] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Stephen O. Ojwach
- a Department of Chemistry , Maseno University , P.O. Box 333, Maseno 40105 , Kenya
- b Department of Chemistry , University of Johannesburg, Auckland Park Kingsway Campus , Auckland Park 2006 , South Africa
| | - George S. Nyamato
- a Department of Chemistry , Maseno University , P.O. Box 333, Maseno 40105 , Kenya
| | - Benard Omondi
- b Department of Chemistry , University of Johannesburg, Auckland Park Kingsway Campus , Auckland Park 2006 , South Africa
| | - James Darkwa
- b Department of Chemistry , University of Johannesburg, Auckland Park Kingsway Campus , Auckland Park 2006 , South Africa
| | - Alexander O. Okoth
- a Department of Chemistry , Maseno University , P.O. Box 333, Maseno 40105 , Kenya
| |
Collapse
|
35
|
Ghorai D, Kumar S, Mani G. Mononuclear, helical binuclear palladium and lithium complexes bearing a new pyrrole-based NNN-pincer ligand: fluxional property. Dalton Trans 2012; 41:9503-12. [DOI: 10.1039/c2dt30816a] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
36
|
Guzei IA, Spencer LC, Munyaneza A, Darkwa J. Ethyl 3-ferrocenyl-1-(pyridin-2-ylmeth-yl)-1H-pyrazole-5-carboxyl-ate. Acta Crystallogr Sect E Struct Rep Online 2012; 68:m35-6. [PMID: 22259337 PMCID: PMC3254307 DOI: 10.1107/s160053681105238x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 12/05/2011] [Indexed: 11/17/2022]
Abstract
The title compound, [Fe(C(5)H(5))(C(17)H(16)N(3)O(2))], crystallizes with an essentially eclipsed conformation of the cyclo-penta-dienyl (Cp) rings. The unsubstituted ring is disordered over two positions with the major component being present 90 (1)% of the time. The substituted Cp ring, the pyrazole ring and three atoms of the eth-oxy-carbonyl group form a conjugated π-system. These 13 atoms are coplanar within 0.09 Å.
Collapse
Affiliation(s)
- Ilia A. Guzei
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI 53706, USA
| | - Lara C. Spencer
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI 53706, USA
| | - Apollinaire Munyaneza
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Johannesburg 2006, South Africa
| | - James Darkwa
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Johannesburg 2006, South Africa
| |
Collapse
|
37
|
|
38
|
Motswainyana WM, Ojwach SO, Onani MO, Iwuoha EI, Darkwa J. Novel hemi-labile pyridyl-imine palladium complexes: Synthesis, molecular structures and reactions with ethylene. Polyhedron 2011. [DOI: 10.1016/j.poly.2011.07.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
39
|
Spectroscopic, structure and DFT studies of palladium(II) complexes with pyridine-type ligands. TRANSIT METAL CHEM 2011. [DOI: 10.1007/s11243-011-9469-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
40
|
Shiotsuki M, Sanda F, Masuda T. Polymerization of substituted acetylenes and features of the formed polymers. Polym Chem 2011. [DOI: 10.1039/c0py00333f] [Citation(s) in RCA: 235] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
This review summarizes the recent advances of substituted polyacetylene chemistry, including new polymerization catalysts and the properties and functions of the polymers.
Collapse
Affiliation(s)
- Masashi Shiotsuki
- Department of Polymer Chemistry
- Graduate School of Engineering
- Kyoto University Katsura Campus
- Kyoto
- Japan
| | - Fumio Sanda
- Department of Polymer Chemistry
- Graduate School of Engineering
- Kyoto University Katsura Campus
- Kyoto
- Japan
| | - Toshio Masuda
- Department of Environmental and Biological Chemistry
- Faculty of Engineering
- Fukui University of Technology
- Fukui
- Japan
| |
Collapse
|
41
|
Ojwach SO, Darkwa J. Pyrazole and (pyrazol-1-yl)metal complexes as carbon–carbon coupling catalysts. Inorganica Chim Acta 2010. [DOI: 10.1016/j.ica.2010.02.014] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
42
|
Miti N, Guzei IA, Nelana SM, Darkwa J. Bis(3,5-dimethylpyrazol-1-yl)alkanones and their reactivity with [PdCl2(NCMe)2]: Isolation of bis(3,5-dimethylpyrazol-1-yl)propan-1-one palladium(II) chloride and C–H activation of propanone linker. INORG CHEM COMMUN 2010. [DOI: 10.1016/j.inoche.2009.10.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
43
|
Ojwach SO, Guzei IA, Darkwa J. (Pyrazol-1-ylmethyl)pyridine palladium complexes: Synthesis, molecular structures, and activation of small molecules. J Organomet Chem 2009. [DOI: 10.1016/j.jorganchem.2008.12.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
44
|
Ojwach SO, Guzei IA, Benade LL, Mapolie SF, Darkwa J. (Pyrazol-1-ylmethyl)pyridine Nickel Complexes: Ethylene Oligomerization and Unusual Friedel−Crafts Alkylation Catalysts. Organometallics 2009. [DOI: 10.1021/om8006322] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Stephen O. Ojwach
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Auckland Park 2006, South Africa, Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, and Department of Chemistry, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - Ilia A. Guzei
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Auckland Park 2006, South Africa, Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, and Department of Chemistry, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - Letitia L. Benade
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Auckland Park 2006, South Africa, Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, and Department of Chemistry, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - Selwyn F. Mapolie
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Auckland Park 2006, South Africa, Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, and Department of Chemistry, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| | - James Darkwa
- Department of Chemistry, University of Johannesburg, Auckland Park Kingsway Campus, Auckland Park 2006, South Africa, Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, and Department of Chemistry, University of Stellenbosch, Private Bag X1, Matieland 7602, South Africa
| |
Collapse
|
45
|
Chitanda JM, Quail JW, Foley SR. Bis[2-phenyl-1-(phenyl-iminio)isoindo-line] di-μ-chlorido-bis-[dichloridopalladate(II)] benzene disolvate. Acta Crystallogr Sect E Struct Rep Online 2008; 64:m907-8. [PMID: 21202770 PMCID: PMC2961759 DOI: 10.1107/s1600536808017005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Accepted: 06/04/2008] [Indexed: 11/30/2022]
Abstract
In the title compound, (C(20)H(17)N(2))(2)[Pd(2)Cl(6)]·2C(6)H(6), the dichloride-bridged [Pd(2)Cl(6)](2-) anion lies across an inversion center with each Pd(II) ion in a slightly distorted square-planar environment. In the crystal structure, two cations and an anion are connected via N-H⋯Cl hydrogen bonds between the NH groups of the iminioisoindoline cations and terminal Cl atoms of a hexa-chloridodipalladate(II) anion. The Pd-Cl distance of the terminal chloride engaged in hydrogen bonding is slightly longer than the Pd-Cl distance of the adjacent terminal chloride which is not involved in hydrogen bonding.
Collapse
Affiliation(s)
- Jackson M. Chitanda
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan, Canada S7N 5C9
| | - J. Wilson Quail
- Saskatchewan Structural Sciences Centre, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan, Canada S7N 5C9
| | - Stephen R. Foley
- Department of Chemistry, University of Saskatchewan, 110 Science Place, Saskatoon, Saskatchewan, Canada S7N 5C9
| |
Collapse
|
46
|
Substituted (pyridinyl)benzoazole palladium complexes: Synthesis and application as Heck coupling catalysts. Polyhedron 2007. [DOI: 10.1016/j.poly.2007.08.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|