Synthesis and Reactivity of Group 12 β-Diketiminate Coordination Complexes

2021 ◽  
Author(s):  
◽  
Dylan Webb
Keyword(s):  
Catalytic Reduction ◽  
Degradation Products ◽  
Lone Pair ◽  
Addition Product ◽  
Addition Reactions ◽  
Metathesis Reaction ◽  
Ancillary Ligands ◽  
Group 12 ◽  
Electronic Stabilization ◽  
Photoluminescence Studies

<p>The variable β-diketiminate ligand poses as a suitable chemical environment to explore unknown reactivity and functionality of metal centres. Variants on the β-diketiminate ligand can provide appropriate steric and electronic stabilization to synthesize a range of β-diketiminate group 12 metal complexes. This project aimed to explore various β-diketiminate ligands as appropriate ancillary ligands to derivatise group 12 element complexes and investigate their reactivity.  A β-diketiminato-mercury(II) chloride, [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]HgCl, was synthesized by addition of [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]Li to mercury dichloride. Attempts to derivatise the β-diketiminato-mercury(II) chloride using salt metathesis reactions were unsuccessful with only β-diketiminate ligand degradation products being observed in the ¹H NMR.  A β-diketiminato-cadmium chloride, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂]CdCl, was derivatized to a β-diketiminato-cadmium phosphanide, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂]Cd P(C₆H₁₁)₂, via a lithium dicyclohexyl phosphanide and a novel β-diketiminato-cadmium hydride, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂]CdH, via Super Hydride. Initial reactivity studies of the novel cadmium hydride with various carbodiimides yielded a β-diketiminato-homonuclear cadmium-cadmium dimer, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂Cd]₂, which formed via catalytic reduction of the cadmium hydride. Attempts to synthesize an amidinate insertion product via a salt metathesis reaction or a ligand exchange reaction proved unsuccessful but a novel cadmium amidinate, [{CH(N-C₆H₁₁)₂}₂{CH(N-C₆H₁₁)(N(H)-C₆H₁₁)}Cd], was synthesized from addition of dicyclohexyl formamidine to bis-hexamethyldisilazane cadmium.  A β-diketiminato-zinc(II) bromide, [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]ZnBr, was synthesized by addition of [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]Li to zinc dibromide. The β-diketiminato-zinc(II) bromide was derivatized to a variety of complexes (including amides and phosphanides) by a salt metathesis reaction. Chalcogen addition reactions were performed from [o-C₆H₄{C(CH₃)=N-2,6-iPr₂C₆H₃}{NH(2,6-iPr₂C₆H₃)}ZnP(C₆H₁₁)₂] to produce double addition products from sulfur, selenium and tellurium. Chalcogen addition reactions from [o-C₆H₄{C(CH₃)=N-2,6-iPr₂C₆H₃}{NH(2,6-iPr₂C₆H₃)}ZnP(C₆H₅)₂] produced a double addition product for selenium and a β-diketiminato-zinc(II) tellunoite bridged dimer, [o-C₆H₄{C(CH₃)=N-2,6-iPr₂C₆H₃}{NH(2,6-iPr₂C₆H₃)}Zn]Te, from tellurium. A total of 14 compounds were characterized via X-ray diffraction. Photoluminescence studies of the β-diketiminato-zinc(II) compounds were conducted where it was proposed that an electron transfer from the lone pair on the hetero-atom influenced the quantum yield and fluorescence intensities.</p>

Synthesis and Reactivity of Group 12 β-Diketiminate Coordination Complexes

2021 ◽  
Author(s):  
◽  
Dylan Webb
Keyword(s):  
Catalytic Reduction ◽  
Degradation Products ◽  
Lone Pair ◽  
Addition Product ◽  
Addition Reactions ◽  
Metathesis Reaction ◽  
Ancillary Ligands ◽  
Group 12 ◽  
Electronic Stabilization ◽  
Photoluminescence Studies

<p>The variable β-diketiminate ligand poses as a suitable chemical environment to explore unknown reactivity and functionality of metal centres. Variants on the β-diketiminate ligand can provide appropriate steric and electronic stabilization to synthesize a range of β-diketiminate group 12 metal complexes. This project aimed to explore various β-diketiminate ligands as appropriate ancillary ligands to derivatise group 12 element complexes and investigate their reactivity.  A β-diketiminato-mercury(II) chloride, [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]HgCl, was synthesized by addition of [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]Li to mercury dichloride. Attempts to derivatise the β-diketiminato-mercury(II) chloride using salt metathesis reactions were unsuccessful with only β-diketiminate ligand degradation products being observed in the ¹H NMR.  A β-diketiminato-cadmium chloride, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂]CdCl, was derivatized to a β-diketiminato-cadmium phosphanide, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂]Cd P(C₆H₁₁)₂, via a lithium dicyclohexyl phosphanide and a novel β-diketiminato-cadmium hydride, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂]CdH, via Super Hydride. Initial reactivity studies of the novel cadmium hydride with various carbodiimides yielded a β-diketiminato-homonuclear cadmium-cadmium dimer, [CH{(CH₃)CN-2,6-iPr₂C₆H₃}₂Cd]₂, which formed via catalytic reduction of the cadmium hydride. Attempts to synthesize an amidinate insertion product via a salt metathesis reaction or a ligand exchange reaction proved unsuccessful but a novel cadmium amidinate, [{CH(N-C₆H₁₁)₂}₂{CH(N-C₆H₁₁)(N(H)-C₆H₁₁)}Cd], was synthesized from addition of dicyclohexyl formamidine to bis-hexamethyldisilazane cadmium.  A β-diketiminato-zinc(II) bromide, [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]ZnBr, was synthesized by addition of [o-C₆H₄{C(CH₃)=N-2,6- iPr₂C₆H₃}{NH(2,6- iPr₂C₆H₃)}]Li to zinc dibromide. The β-diketiminato-zinc(II) bromide was derivatized to a variety of complexes (including amides and phosphanides) by a salt metathesis reaction. Chalcogen addition reactions were performed from [o-C₆H₄{C(CH₃)=N-2,6-iPr₂C₆H₃}{NH(2,6-iPr₂C₆H₃)}ZnP(C₆H₁₁)₂] to produce double addition products from sulfur, selenium and tellurium. Chalcogen addition reactions from [o-C₆H₄{C(CH₃)=N-2,6-iPr₂C₆H₃}{NH(2,6-iPr₂C₆H₃)}ZnP(C₆H₅)₂] produced a double addition product for selenium and a β-diketiminato-zinc(II) tellunoite bridged dimer, [o-C₆H₄{C(CH₃)=N-2,6-iPr₂C₆H₃}{NH(2,6-iPr₂C₆H₃)}Zn]Te, from tellurium. A total of 14 compounds were characterized via X-ray diffraction. Photoluminescence studies of the β-diketiminato-zinc(II) compounds were conducted where it was proposed that an electron transfer from the lone pair on the hetero-atom influenced the quantum yield and fluorescence intensities.</p>

Ionic dimerisation of trifluoropropenenitrile and its addition reactions with methyl trifluoropropenoate

1980 ◽  
Vol 45 (2) ◽  
pp. 406-414 ◽  
Author(s):  
Jiří Svoboda ◽  
Oldřich Paleta ◽  
Václav Dědek
Keyword(s):  
Reaction Mechanism ◽  
Proton Transfer ◽  
Substituent Effect ◽  
Solvent Molecule ◽  
Addition Product ◽  
Potassium Fluoride ◽  
Relative Reactivity ◽  
Addition Reactions ◽  
Tertiary Amines ◽  
Optimum Conditions

Dimerisation of trifluoropropenenitrile (I) in the presence of potassium fluoride and tertiary amines afforded a mixture of stereoisomeric perfluoro-4-methyl-pentenedinitriles (II), higher-boiling compounds, and 2,3,3,3-tetrafluoropropanenitrile (III) which arises by proton transfer from the solvent molecule. Under optimum conditions, product II was obtained in about 50% yield. Reaction of the nitrile I with methyl trifluoropropenoate (IV) gave, besides the dimers II and V, the product of addition of the nitrile I to the propenoate, IV, i.e. methyl 4-cyanoperfluoro-2-pentenoate (VI), and the addition product of the propenoate IV to the nitrile I, i.e. methyl 4-cyanoperfluoro-2-methyl-3-butenoate (VII). The relative reactivity if I and IV is discussed. The ratio of stereoisomers in II, V, VI and VII indicates that the magnitude of the steric substituent effect, operating in the reaction mechanism, decreases in the order -CFCF3.(COOCH3) > -CFCF3(CN) > -COOCH3 > -CN.

Structural and Spectroscopic Impact of Tuning the Stereochemical Activity of the Lone Pair in Lead(II) Cyanoaurate Coordination Polymers via Ancillary Ligands

2008 ◽  
Vol 47 (14) ◽  
pp. 6353-6363 ◽  
Author(s):  
Michael J. Katz ◽  
Vladimir K. Michaelis ◽  
Pedro M. Aguiar ◽  
Renante Yson ◽  
Haiyan Lu ◽  
...  
Keyword(s):  
Coordination Polymers ◽  
Lone Pair ◽  
Ancillary Ligands ◽  
Stereochemical Activity

scholarly journals Comparative analysis of biological versus chemical synthesis of palladium nanoparticles for catalysis of chromium (VI) reduction

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mpumelelo T. Matsena ◽  
Evans M. N. Chirwa
Keyword(s):  
Rate Constant ◽  
Catalytic Reduction ◽  
Anthropogenic Activities ◽  
Cost Effective ◽  
Addition Product ◽  
Pd Nanoparticles ◽  
Product Inhibition ◽  
Chromium Vi ◽  
Langmuir Hinshelwood Mechanism ◽  
The One

AbstractThe discharge of hexavalent chromium [Cr(VI)] from several anthropogenic activities leads to environmental pollution. In this study, we explore a simple yet cost effective method for the synthesis of palladium (Pd) nanoparticles for the treatment of Cr(VI). The presence of elemental Pd [Pd(0)] was confirmed by scanning electron microscope (SEM), electron dispersive spectroscopy and X-ray diffraction (XRD). We show here that the biologically synthesized nanoparticles (Bio-PdNPs) exhibit improved catalytic reduction of Cr(VI) due to their size being smaller and also being highly dispersed as compared to chemically synthesized nanoparticles (Chem-PdNPs). The Langmuir–Hinshelwood mechanism was successfully used to model the kinetics. Using this model, the Bio-PdNPs were shown to perform better than Chem-PdNPs due to the rate constant (kbio = 6.37 mmol s−1 m−2) and Cr(VI) adsorption constant (KCr(VI),bio = 3.11 × 10−2 L mmol−1) of Bio-PdNPs being higher than the rate constant (kchem = 3.83 mmol s−1 m−2) and Cr(VI) adsorption constant (KCr(VI),chem = 1.14 × 10−2 L mmol−1) of Chem-PdNPs. In addition, product inhibition by trivalent chromium [Cr(III)] was high in Chem-PdNPs as indicated by the high adsorption constant of Cr(III) in Chem-PdNPs of KCr(III),chem = 52.9 L mmol−1 as compared to the one for Bio-PdNPs of KCr(III),bio = 2.76 L mmol−1.

scholarly journals Applicability of Reddish Orange Light Emitting Samarium (III) Complexes For Biomedical and Multifunctional Optoelectronic Devices

2021 ◽  
Author(s):  
Pooja Hooda ◽  
V. B. Taxak ◽  
R. K. Malik ◽  
Savita Khatri ◽  
Poonam Kumari ◽  
...  
Keyword(s):  
Quantum Yield ◽  
Band Gap ◽  
Energy Band ◽  
Biological Properties ◽  
Energy Band Gap ◽  
Ancillary Ligands ◽  
Time Quantum ◽  
Lighting Systems ◽  
Photoluminescence Studies ◽  
Reddish Orange

Abstract Six crimson samarium (III) complexes based on β-ketone carboxylic acid and ancillary ligands were synthesized by adopting grinding technique. All synthesized complexes were investigated via employing elemental analysis, infrared, UV-Vis, NMR, TG/DTG and photoluminescence studies. Optical properties of these photostimulated samarium (III) complexes exhibit reddish-orange luminescence due to 4G5/2→6H7/2 transition at 606 nm of samarium (III) ions. Further, energy band gap, color purity, CIE color coordinates, CCT and quantum yield of all complexes were determined accurately. Replacement of water molecules by ancillary ligands enriched the complexes (S2-S6) with decay time, quantum yield, luminescence, energy band gap and biological properties than parent complex (S1). Interestingly, these efficient properties of complexes may find their applications in optoelectronic and lighting systems. In addition to these the antioxidant and antimicrobial assays were also investigated to explore the application in biological assays.

Grignard Addition Reactions to 1,4-Difunctionalized But-2-ynes

1993 ◽  
Vol 46 (11) ◽  
pp. 1657 ◽  
Author(s):  
AN Desilva ◽  
CL Francis ◽  
AD Ward
Keyword(s):  
Good Yield ◽  
Addition Product ◽  
Grignard Reagents ◽  
High Yield ◽  
Addition Reactions ◽  
Grignard Addition ◽  
Trisubstituted Alkenes ◽  
Phenylmagnesium Bromide

Trisubstituted alkenes of E geometry have been prepared by anti addition of Grignard reagents to 1,4-difunctionalized but-2-ynes. Addition of primary, secondary and aromatic Grignard reagents to but-2-yne-1,4-diol provided (E)-2-substituted but-2-ene-1,4-diols as major products along with the corresponding 2-substituted buta-2,3-dien-1-ols. Addition of phenylmagnesium bromide to the mono- and di-methyl ethers of but-2-yne-1,4-diol gave 2,3-diphenyl-1,3-diene. Treatment of 4-dimethylaminobut-2-yn-1-ol with primary alkyl and alkenyl Grignard reagents afforded the 2-substituted anti addition product regiospecifically, stereospecifically and in high yield. Reaction of 1-dimethylamino-4-methoxybut-2-yne with butylmagnesium bromide provided only the 3-substituted anti addition product in good yield.

scholarly journals Water Treatment Using Integrated Catalytic Reduction/Oxidation and Biofiltration Processes

Proceedings ◽  
2020 ◽  
Vol 57 (1) ◽  
pp. 29
Author(s):  
Irina Fierascu ◽  
Roxana Ioana Brazdis ◽  
Anda Maria Baroi ◽  
Toma Fistos ◽  
Corina Bradu ◽  
...  
Keyword(s):  
Water Treatment ◽  
Organic Compounds ◽  
Catalytic Reduction ◽  
Degradation Products ◽  
Water Sources ◽  
Chlorinated Organic Compounds ◽  
Chlorinated Organic ◽  
Nitrogen Ions

Pollution of water sources with nitrogen ions and chlorinated organic compounds (COCl), such as some pesticides or their degradation products [...]

Sign in / Sign up

Export Citation Format

Share Document