Academic literature on the topic 'Aldimine ligands'
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Journal articles on the topic "Aldimine ligands"
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Brewer, Greg, Cynthia Brewer, Raymond J. Butcher, and Peter Zavalij. "Formation of Ketimines from Aldimines in Schiff Base Condensation of Amino Acids and Imidazole-2-Carboxaldehydes: Tautomerization of Schiff Bases of Amino Acids Resulting in the Loss of Stereogenic Center." Inorganics 11, no. 10 (2023): 381. http://dx.doi.org/10.3390/inorganics11100381.
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The Schiff base reaction of imidazole-2-carboxaldehydes with the anion of alanine, leucine and phenylalanine in the presence of nickel(II) ion gives the neutral NiL2 complexes. The Schiff base ligand, L, binds through an imidazole nitrogen, NIm, the amino acid nitrogen, NAA, and a carboxylate oxygen, O, atom. The two N2O ligands bind to the nickel(II) in a meridional fashion with the NIm and O of each ligand in trans positions. These ligands can exist as the anticipated aldimine, Im − CH = NAA − CH(R) − CO2−, or the ketimine, Im − CH2NAA = C(R) − CO2−, tautomer. Tautomerization of the initially formed aldimine Schiff base results in movement of the hydrogen atom of the alpha carbon of the amino acid to the aldehyde carbon, CAld, atom of the imidazole carboxaldehyde with resultant relocation of the imine double bond in the reverse direction. Ten structures of the structurally unprecedented ketimine tautomer, prepared from imidazole-2-carboxaldehydes and a pyrazole-3-carboxaldehyde, were presented. The structural data supported the formation of the ketimines in each case, while the aldimine tautomer was observed with imidazole-4-carboxaldehydes. A rationale of this can be explained on the basis of charge distribution in the likely intermediate in the tautomerization.
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Hanessian, Stephen, Eric Jnoff, Noemy Bernstein, and Michel Simard. "Bifunctional bis(oxazolines) as potential ligands in catalytic asymmetric reactions." Canadian Journal of Chemistry 82, no. 2 (2004): 306–13. http://dx.doi.org/10.1139/v03-198.
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C2-symmetrical bis(oxazoline) ligands bearing pendant alkylthio ether groups were synthesized, and the structures of Cu complexes were determined by single crystal X-ray diffraction. The potential utility in catalysis was shown in the asymmetric addition of methyllithium to an aromatic aldimine, which resulted in a mixture of products with an enantiomeric excess of 68%.Key words: two-center catalysis, bis(oxazoline), aldimine, imine alkylation.
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ALI, Uzma, Aneela MAALIK, Muhammad Babar TAJ, et al. "Facile synthesis, solublization studies and anti-inflammatory activity of amorphous zinc(II) centered aldimine complexes." Revue Roumaine de Chimie 65, no. 10 (2021): 929–41. http://dx.doi.org/10.33224/rrch.2020.65.10.08.
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In this study, Zn(II) centered complexes with aldimine derivatives were synthesized using green solvent, polyethylene glycol (PEG-400) and amorphous complexes were characterized by FT-IR, multinuclear (1H and 13C NMR), elemental and thermal analysis. Thermogravimetric analysis indicated the extended thermal stability of the synthesized complexes. All the Zn(II) complexes show very significant photoexcitation in the range of 318 – 384 nm and photoemission in the range of 502 – 562 nm. Among all the complexes, Zn(II) complex (3Zn) showed minimum band gap value, 2.35 eV. These amorphous complexes have been reported for their wide applications in biomedical sciences. The synthesized aldimine ligands and Zn(II) complexes were investigated for anti-inflammatory activity and these complexes showed more anti-inflammatory potential than the corresponding aldimine ligands. The solubilization of zinc complexes in sodium dodecyl sulphate was also investigated to reveal the interaction of metal complexes by using UV-Visible spectroscopy and electrical conductivity measurements.
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Dutta, Jayita, Michael G. Richmond, and Samaresh Bhattacharya. "Palladium(0)-mediated C–H bond activation of N-(naphthyl)salicylaldimine and related ligands: utilization of the resulting organopalladium complexes in catalytic C–C and C–N coupling reactions." Dalton Transactions 44, no. 30 (2015): 13615–32. http://dx.doi.org/10.1039/c5dt01564b.
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Wu, Rui, Ruslan Sanishvili, Boris R. Belitsky, et al. "PLP and GABA trigger GabR-mediated transcription regulation in Bacillus subtilis via external aldimine formation." Proceedings of the National Academy of Sciences 114, no. 15 (2017): 3891–96. http://dx.doi.org/10.1073/pnas.1703019114.
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The Bacillus subtilis protein regulator of the gabTD operon and its own gene (GabR) is a transcriptional activator that regulates transcription of γ-aminobutyric acid aminotransferase (GABA-AT; GabT) upon interactions with pyridoxal-5′-phosphate (PLP) and GABA, and thereby promotes the biosynthesis of glutamate from GABA. We show here that the external aldimine formed between PLP and GABA is apparently responsible for triggering the GabR-mediated transcription activation. Details of the “active site” in the structure of the GabR effector-binding/oligomerization (Eb/O) domain suggest that binding a monocarboxylic γ-amino acid such as GABA should be preferred over dicarboxylic acid ligands. A reactive GABA analog, (S)-4-amino-5-fluoropentanoic acid (AFPA), was used as a molecular probe to examine the reactivity of PLP in both GabR and a homologous aspartate aminotransferase (Asp-AT) from Escherichia coli as a control. A comparison between the structures of the Eb/O–PLP–AFPA complex and Asp-AT–PLP–AFPA complex revealed that GabR is incapable of facilitating further steps of the transamination reaction after the formation of the external aldimine. Results of in vitro and in vivo assays using full-length GabR support the conclusion that AFPA is an agonistic ligand capable of triggering GabR-mediated transcription activation via formation of an external aldimine with PLP.
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Taj, Muhammad Babar, Muneera D. F. Alkahtani, Uzma Ali, et al. "New Heteroleptic 3D Metal Complexes: Synthesis, Antimicrobial and Solubilization Parameters." Molecules 25, no. 18 (2020): 4252. http://dx.doi.org/10.3390/molecules25184252.
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The microbial resistance to current antibiotics is increasing day by day, which in turn accelerating the development of new effective drugs. Several studies have proved the high antimicrobial potential of the interaction of several organic ligands with a variety of metal ions. In the present study, a conventional method has been adopted in the synthesis of twelve new heteroleptic complexes of cobalt (II), nickel (II), copper (II) and zinc (II) using three aldimines, namely, (HL1 ((E)-2-((4-chloro-2-hydroxybenzylidene)amino)-3,4-dimethyl-5-phenylcyclopent-2-en-1-one), HL2 ((Z)-3-((4-chlorobenzylidene)amino)-4-hydroxy-5-nitrobenzenesulfonic acid) HL3 (2,2′-((1,2-phenylenebis(azaneylylidene))bis(methaneylylidene))diphenol)) as primary ligands, while phenyl glycine was the secondary ligand. The synthesized compounds were characterized by UV-vis, IR and multinuclear (1H and 13C) NMR spectroscopy, elemental analysis, and electrical conductance. The IR study revealed the coordination of the aldimine derivatives with the -OH and N atom of imine moiety. In contrary to this, the phenyl glycine coordinated to the metal ions via oxygen of carboxylate and nitrogen of the amino group. The spectroscopic analysis unveiled the tetrahedral geometry of the synthesized metal (II) complexes, except for ligand HL3 which exhibited octahedral geometry. The synthesized compounds generally showed antibacterial activity for all microbes, except Ni (II) complexes lacking sensitivity. Furthermore, to access the bioavailability, the synthesized complexes were screened for their solubilization in the micellar media of sodium lauryl sulphate. The metal complex–surfactant interaction was revealed by UV-vis spectroscopy and electrical conductivity measurements.
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Rath, Sankar P., Sujit Mondal, and Tapas Ghosh. "Mixed-ligand oxovanadium(V) complexes incorporating bidentate salicylaldehyde and tridentate aldimine ligands." Transition Metal Chemistry 21, no. 4 (1996): 309–11. http://dx.doi.org/10.1007/bf00139024.
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Wosińska-Hrydczuk, Marzena, and Jacek Skarżewski. "New Nitrogen, Sulfur-, and Selenium-Donating Ligands Derived from Chiral Pyridine Amino Alcohols. Synthesis and Catalytic Activity in Asymmetric Allylic Alkylation." Molecules 26, no. 12 (2021): 3493. http://dx.doi.org/10.3390/molecules26123493.
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Although many chiral ligands for asymmetric catalysis have been developed, there is still a need for new structures allowing the modular approach. Recently, easy synthesis of chiral pyridine-containing β-amino alcohols has been elaborated by opening respective epoxides with enantiomeric 1-phenylethylamine. This paper reports the synthetic transformation of β-amino alcohols into the new complexing pyridine-containing seleno- and thioethers. The amino alcohols were effectively converted to cyclic sulfonamidates, which were reacted with thiolates or phenyl selenide nucleophile. The reaction was diastereoselective, and its outcome depended on the configuration at the substitution center. The problem was discussed considering DFT optimized structures of both diastereomeric sulfonamidates. New amino-aldimine ligands were also synthesized from chiral pyridine-containing diamines. Nine new chiral ligands were tested in the Tsuji-Trost allylic alkylation resulting in the enantiomerically enriched product in up to 75% ee. The observed stereochemical induction agrees with the prevailing nucleophilic attack at the allylic carbon laying opposite to the complexing nitrogen of pyridine in η3-allylic intermediate complexes.
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Zhou, Xiaoyu, Jiaxin Yang, Zhiqiang Hao, Zhangang Han, Jin Lin, and Guo-Liang Lu. "Copper Complexes with N,N,N-Tridentate Quinolinyl Anilido-Imine Ligands: Synthesis and Their Catalytic Application in Chan−Lam Reactions." Molecules 28, no. 21 (2023): 7406. http://dx.doi.org/10.3390/molecules28217406.
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The treatment of 2-(ArNC(H))C6H4-HNC9H6N with n-BuLi and the subsequent addition of CuCl2 afforded the anilido-aldimine Cu(II) complexes 1-5 Cu[{2-[ArN=C(H)]C6H4}N(8-C9H6N)]Cl (Ar = 2,6-iPr2C6H3 (1), 2,4,6-(CH3)3C6H2 (2), 4-OCH3C6H4 (3), 4-BrC6H4 (4), 4-ClC6H4 (5)), respectively. All the copper complexes were fully characterized by IR, EPR and HR-MS spectra. The X-ray diffraction analysis reveals that 2 and 4 are mononuclear complexes, and the Cu atom is sitting in a slightly square-planar geometry. These Cu(II) complexes have exhibited excellent catalytic activity in the Chan–Lam coupling reactions of benzimidazole derivatives with arylboronic acids, achieving the highest yields of up to 96%.
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Agarwal, Ram K., and Surendra Prasad. "Synthesis, Spectroscopic and Physicochemical Characterization and Biological Activity of Co(II) and Ni(II) Coordination Compounds with 4-Aminoantipyrine Thiosemicarbazone." Bioinorganic Chemistry and Applications 3, no. 3-4 (2005): 271–88. http://dx.doi.org/10.1155/bca.2005.271.
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We describe the synthesis and characterization of cobalt(II) and nickel(II) coordination compounds of 4[N-(furan-2’-aldimine)amino]antipyrine thiosemicarbazone (FFAAPTS) and 4[N-(4'-nitrobenzalidene) amino]antipyrine thiosemicarbazone (4'-NO2BAAPTS). All the isolated compounds have the general composition MX2(L)(H2O) (M = Co2+or Ni2+; X = Cl, Br, NO3, NCS or CH3COO; L = FFAAPTS or 4'-NO2BAAPTS) and M(ClO4)2(L)2(M = Co2+or Ni2+; L = FFAAPTS or 4'-NO2BAAPTS). Infrared spectral studies indicate that both the thiosemicarbazones coordinate in their neutral form and they act as {N,N,S} tridentate chelating ligands. Room temperature magnetic measurements and electronic spectral studies suggest the distorted octahedral geometries of the prepared complexes. Thermogravimetric studies are also reported and the possible structures of the complexes are proposed. Antibacterial and antifungal properties of these metal-coordination compounds have also been studied.
Dissertations / Theses on the topic "Aldimine ligands"
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Ali, Md Afsar. "Synthetic, physico-chemical and reactivity aspects of co-ordination compounds of molybdenum and dioxounarium (vi) with pterin and aldimine ligands." Thesis, University of North Bengal, 2008. http://hdl.handle.net/123456789/1303.
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Reich, Blair Jesse Ellyn. "Cyanide-catalyzed C-C bond formation: synthesis of novel compounds, materials and ligands for homogeneous catalysis." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4987.
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Cyanide-catalyzed aldimine coupling was employed to synthesize compounds
with 1,2-ene-diamine and ñ-imine-amine structural motifs: 1,2,N,N'-
tetraphenyletheylene-1,2-diamine (13) and (+/-)-2,3-di-(2-hydroxyphenyl)-1,2-
dihydroquinoxaline (17), respectively. Single crystal X-ray diffraction provided solidstate
structures and density functional theory calculations were used to probe isomeric
preferences within this and the related hydroxy-ketone/ene-diol system. The enediamine
and imine-amine core structures were calculated to be essentially identical in
energy. However, additional effects-such as ÃÂ conjugation-in 13 render an enediamine
structure that is slightly more stable than the imine-amine tautomer (14). In
contrast, the intramolecular hydrogen bonding present in 17 significantly favors the
imine-amine isomer over the ene-diamine tautomer (18).
Aldimine coupling (AIC) is the nitrogen analogue of the benzoin condensation
and has been applied to dialdimines, providing the first examples of cyclizations effected
by cyanide-catalyzed AIC. Sodium cyanide promoted the facile, intramolecular
cyclization of several dialdimines in N,N-dimethylformamide, methanol, or
dichloromethane/water (phase-transfer conditions) yielding a variety of six-membered
heterocycles. Under aerobic conditions, an oxidative cyclization occurs to provide the
diimine heterocycle.
Cyanide-catalyzed aldimine coupling was employed as a new synthetic method
for oligomerization. Nine rigidly spaced dialdimines were oxidatively coupled under
aerobic conditions to yield conjugated oligoketimines and polyketimines with
unprecedented structure and molecular weight (DP = 2 - 23, ~700 -8200 g/mol). The ñ- diimine linkage was established based on IR spectroscopy, NMR spectroscopy, size
exclusion chromatography, and X-ray crystallographic characterization of the model
oxidized dimer of N-benzylidene-(p-phenoxy)-aniline. Cyclic voltammetry indicates ptype
electrical conductivity, suggesting they are promising candidates for plastic
electronic devices.
The cyanide-catalyzed benzoin condensation reaction of 4-substituted
benzaldehydes followed by oxidation to the diketone, and the Schiff Base condensation
of two equivalents of o-aminophenol provides 2,3-(4-X-phenyl)2-1,4-(2-
hydroxyphenyl)2-1,4-diazabutadiene. The ligand is given the moniker X-dabphol.
These ligands are readily metallated to form M-X-dabphol complexes. The copper
complexes catalytically fix CO2 with propylene oxide to yield propylene carbonate. DFT
studies along with a comparison with Hammet parameters help validate and elaborate on
the catalytic cycle and the catalytic results obtained. The nickel complex is competent
for olefin epoxidation. Synthesis, characterization, X-ray structure, DFT analysis, and
catalytic activity of the parent nickel dabphol complex are reported.
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Rahman, Mohammed Mahmudur. "Zwitterionic late transition metal alkene polymerisation catalysts containing aminofulvene-aldiminate (AFA) ligands." Thesis, University of Edinburgh, 2010. http://hdl.handle.net/1842/4895.
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Over recent years significant progress has been made in the design and development of late transition metal cationic catalysts for olefin polymerisation. Never-the-less, the activation of catalyst precursors and generation of active species still remains a challenge. In this respect, zwitterionic catalysts could offer a range of advantages over the traditional two component catalytic systems. For example, stable zwitterions are well-defined, single component catalysts which do not require Lewis acid co-catalysts for activation. Therefore, this eliminates the possibility of anions coordinating to the active site and could provide highly active catalysts. Moreover, this could reduce the production costs. In this thesis the 6-aminofulvene-2-aldiminate (AFA) ligand system has been employed to develop zwitterionic, charge-neutral complexes, analogues of Brookhart-type cationic alkene polymerisation catalyst containing 1,2-diimine ligand. Chapter 1 of the thesis provides a comprehensive literature review of the late transition metal (Group 10) α-diimine catalytic systems and the zwitterionic early and late transition metal alkene polymerisation catalysts. Chapter 2 describes the synthesis and characterisation of some novel zwitterionic complexes [(Ph2AFA)Pd(Me)(DMAP)], [(Ph2AFA)(N,N-dimethylbenzylamine-2-C,N)- Pd(II)] and [(Ph2AFA)Ni(η 3-C3H5)] and their possible application as catalyst precursors in alkene polymerisation. In principle, upon activation these complexes should exhibit higher catalytic activity. The ideal catalyst precursor for a highly active palladium based system would be a halide-bridged dimer of the form [(Ph2AFA)Pd(μ-X)]2. Chapter 2 describes several efforts towards the synthesis of such complexes using a range of R2AFA ligands. Even with the introduction of bulky N-substituents such as cyclohexyl or tert-butyl, the halidebridged dimers could not be synthesised. Instead, the reaction between the deprotonated ligand and [PdCl2(NCPh)2] provides bis-chelated complexes [(R2AFA)2Pd]. In order to introduce more steric bulk into the AFAH ligand which might lead to a halide-bridged dimer, two more ligands N,N’-bis(2,6-diisopropyl)phenyl-6-aminofulvene-2-aldimine and N,N’-di-(2,4,6-trimethyl)phenyl-6-aminofulvene-2-aldimine have been synthesised and characterised. It has been found that the presence of the 2,6-diisopropylphenyl substituents in N,N'-bis(2,6-diisopropyl)phenyl-6-aminofulvene-2-aldimine not only prevents the coordination of two ligands to the same metal, but precludes complexation all together. Chapter 2 also describes several efforts to develop a hemi-labile complex for alkene polymerisation. Chapter 3 describes the synthesis of metalloligands of aminofulvene-aldimine (AFA) and corresponding bimetallic complexes. The AFA ligand affords transition metal complexes via both η 5- as well as κ 2-coordination modes. A new synthetic methodology has been developed to synthesise metalloligands [Cp*RuII(Ph2AFA)H][BF4], [Cp*RhIII(Cy2AFA)H][BF4]2 and [Cp*RhIII(Cy2AFA)]- [BF4]. The basicity of the monocationic Rh metalloligand is found to be significantly lower than that of its Ru analogues. This is significant as it opens a potentially easy synthetic route to bimetallic complexes. The bimetallic complex [Cp*RhIII(Cy2AFAPdCl2)][BF4] has been developed for alkene polymerisation in an attempt to investigate the charge effect in alkene polymerisation catalysis. Upon activation this monocationic Rh/Pd bimetallic complex would provide a dicationic active species which would in principle be a more highly active catalyst than the Brookhart mono cationic diimine catalysts. Chapter 4 describes all the experimental procedure and polymerisation tests in this thesis.
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Mabad, Bouchra. "Modelisation du site d'oxydation de l'eau en photosynthese : complexes du manganese avec des bases de schiff polydentees." Toulouse 3, 1987. http://www.theses.fr/1987TOU30103.
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Bedioui, Fethi. "Etude électrochimique de complexes de métaux de transition (bases de Schiff et porphyrines) en solution et sous forme d'électrodes modifiées : application à la catalyse électroassistée de réactions organiques." Paris 6, 1986. http://www.theses.fr/1986PA066338.
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Les propriétés électrochimiques des complexes co-base de Schiff (phenylene-bis(salicylideneiminoto)-co, ou Co(II)saloph, et n-methylenepropylene-bis-(salicylideneiminoto)-co, ou co-selnmedpt) et de tetraphenylporphine-co, ou CoTPP, sont utilisées pour étudier la réduction électroassistée d'halogénures organiques, Rx, avec un catalyseur fixe sur support conducteur, en milieu organique. On étudie: 1) la réduction du chlorure de benzyle électrocatalysée par des électrodes de graphite modifiées par du co-saloph et 2) l'oxydation par l'oxygène moléculaire du di-tert-butylphenol, électrocatalysée par des films de polypyrrole contenant la porphyrine mntcpp.
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Tsai, Yueh-Hsuan, та 蔡岳軒. "Synthesis and Structural Studies of Metal Complexes with O,O,O-Tridentate Bis(phenolate) and N,N,N-Anilido-Aldimine Ligands: Their Application in the Ring-Opening Polymerization of L-Lactide and ε-Caprolactone". Thesis, 2009. http://ndltd.ncl.edu.tw/handle/40546458297240636656.
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碩士<br>國立中興大學<br>化學系所<br>97<br>A family of metal complexes of the type ([(L1-H)Li]2 (1), [(L1-H)Li(THF)]2 (2), [(L1-H)Li(BnOH)]2 (3), [L1Zn]2 (4), [L1AlOBn]2 (5), L2MgBu (6) and L2ZnEt (7)), where L1-H2 = O,O,O-tridentate bis(phenolate) ligand and L2-H = N,N,N-anilido-aldimine ligand, has been synthesized and characterized, including a structural determination of complexes 1, 2, 3, 5, 6 and 7. Their suitability for initiating the ring-opening polymerization (ROP) of L-lactide (LA) and ε-caprolactone (CL) has been investigated in the presence or absence of benzyl alcohol (BnOH). All the metal complexes have shown efficient and controlled activity toward the ring-opening polymerization of cyclicesters as shown by the linear relationship between the percentage conversion and the number-average molecular weight in short period of time. In the anilido–aldimine system, the activity of magnesium complex is higher than that of zinc complex, which is probably due to the better Lewis acidity and more oxophilic nature of magnesium metal. And for bis(phenolate) system, the activity of lithium complex is investigated for ROP of lactide where as aluminium and zinc complexes used for ROP of caprolactone. The polymerization kinetics using complex 7 in the presence of BnOH as an initiator was also studied, and the experimental results reveal that the rate of reaction is first-order dependence on monomer and second-order dependency on catalyst 7 concentration. On the basis of literature report, polymerization results and crystal structure of 2 and 3, a mechanism for ROP of lactide has been proposed.
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Yang, Chih-Wei, and 楊志偉. "Coordination Chemistry of a 5-tert-Butyl-2-[(2,6-diisopropylphenyl)aldimino]-pyrrolate Ligand." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/58264181135801681221.
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碩士<br>國立中山大學<br>化學系研究所<br>90<br>The Vilsmeier-Haack reaction of pyrrole with oxalyl chloride and N,N-dimethylformaldehyde followed by Friedel-Crafts alkylation with Me3CCl in the presence of AlCl3 afforded 5-tert-butylpyrrole-2- carbal- dehyde in high yields. Condensation reactions of 5-tert-butylpyrrole-2- carbaldehyde with 2,6-diisopropylaniline produced 5-tert-Butyl-2-2[(2,6- diisopropylphenyl)aldimino]pyrrole (HL). Protonolysis of MgnBu2 with HL yielded the bis(iminopyrrolate) complex MgL2 (1) as a colorless crystalline solid. In situ lithiation of HL followed by addition of one equivalent of ZrCl4 or AlCl3 led to the mono(iminopyrrolate) complexes ZrLCl4Li(OEt2)2 (2) and AlLCl2 (3) , respectively. Treatment of 3 with two equivalents of MeMgBr produced AlLMe2 (4). In addition to the spectroscopic data, all metal complexes were characterized by X-ray crystallography.
Book chapters on the topic "Aldimine ligands"
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Benkoski, Léa, and Tristan H. Lambert. "Construction of Multiple Stereocenters." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0039.
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Erick M. Carreira at ETH Zürich reported (Science 2013, 340, 1065) the enantioselective α-allylation of aldehyde 1 with alcohol 2 to produce 3 using a dual catalytic system involving a chiral iridium complex and amine 5. This stereodivergent method allows access to all of the possible stereoisomers of 3. In a conceptually related process, John F. Hartwig at the University of California, Berkeley reported (J. Am. Chem. Soc. 2013, 135, 2068) the highly stereoselective allylic alkylation of azlactone 6 with allylic carbonate 7 catalyzed by a combination of Ir(cod)Cl₂, ligand 9, and racemic silver phosphate 10. An enantioselective three-component Mannich-type reaction of tert-butyl diazoacetate, aniline, and imine 11 to produce α,β-bis(arylamino) acid derivative 13 under dual catalysis with Rh₂(OAc)₄ and acid 12 was developed (Synthesis 2013, 45, 452) by Wenhao Hu at the Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development. Keiji Maruoka at Kyoto University reported (Chem. Commun. 2013, 49, 1118) a one-pot cross double-Mannich reaction of acetylaldehyde 14, and imines 16 and 17 using axially chiral amino sulfonamide 15 to obtain densely functionalized 1,3-diamine 18 as a single stereoisomer. Jeffrey S. Johnson at the University of North Carolina at Chapel Hill reported (Org. Lett. 2013, 15, 2446) the asymmetric synthesis of enantioenriched anti-α-hydroxy-β-amino acid derivative 21 from 19 by treatment with oxone followed by catalytic hydrogenation using Ru(II) complex 20. Naoya Kumagai and Masakatsu Shibasaki at the Institute of Microbial Chemistry found (Org. Lett. 2013, 15, 2632) that a silver complex of bisphosphine 24 effected a syn-selective and highly enantioselective Mannich-type reaction of aldimine 22 and α-sulfanyl lactone 23 to furnish the stereodiad 25 with very high ee. The enantioselective homocrotylation of octanal 26 with cyclopropylcarbinylboronate 27 to produce alcohol 28 with high ee was disclosed (J. Am. Chem. Soc. 2013, 135, 82) by Isaac J. Krauss at Brandeis University with computational studies provided by Kendall N. Houk at UCLA. Benjamin List at the Max-Planck-Institut für Kohlenforschung reported (J. Am. Chem. Soc. 2013, 135, 6677) the enantioselective epoxidation of cyclohexenone 29 utilizing cinchona alkaloid- derived catalyst 30.