- A Fluorine-18 Radiolabeling Method Enabled by Rhenium(I) Complexation Circumvents the Requirement of Anhydrous Conditions
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Azeotropic distillation is typically required to achieve fluorine-18 radiolabeling during the production of positron emission tomography (PET) imaging agents. However, this time-consuming process also limits fluorine-18 incorporation, due to radioactive decay of the isotope and its adsorption to the drying vessel. In addressing these limitations, the fluorine-18 radiolabeling of one model rhenium(I) complex is reported here, which is significantly improved under conditions that do not require azeotropic drying. This work could open a route towards the investigation of a simplified metal-mediated late-stage radiofluorination method, which would expand upon the accessibility of new PET and PET-optical probes.
- Klenner, Mitchell A.,Pascali, Giancarlo,Zhang, Bo,Sia, Tiffany R.,Spare, Lawson K.,Krause-Heuer, Anwen M.,Aldrich-Wright, Janice R.,Greguric, Ivan,Guastella, Adam J.,Massi, Massimiliano,Fraser, Benjamin H.
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Read Online
- Formation of 1,10-phenanthroline-N,N′-dioxide under mild conditions: The kinetics and mechanism of the oxidation of 1,10-phenanthroline by peroxomonosulfate ion (Oxone)
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This paper confirms the unexpected formation of 1,10-phenanthroline-N,N′-dioxide (phenO2) when 1,10-phenanthroline (phen) is oxidized by peroxomonosulfate ion (PMS) in a neutral aqueous solution. The kinetics of oxidation of phen by PMS feature
- Bellér, Gábor,Szabó, Mária,Lente, Gábor,Fábián, István
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- 1-Methyl-1,10-phenanthrolin-2(1H)-one (L) as a ligand to Eu(III): Crystal structure and luminescent properties of [Eu(L)3(NO3) 3] Dedicated to Professor George Christou on the occasion of his 60th birthday.
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A new coordination compound of Eu(III) with 1-methyl-1,10-phenanthroline- 2(1H)-one (L) as a ligand has been synthesized and characterized using infrared spectroscopy, elemental analysis and single crystal X-ray diffraction. The structure contains isolated [Eu(L)3(NO3)3] molecules interacting through extensive π-stacking. Photoluminescence studies demonstrate that the complex shows line-like emission characteristic of Eu(III) when excited in the ligand-centered absorption bands, with a quantum yield of 22% and a lifetime of 0.74 ms.
- Akerboom, Sebastiaan,Van Den Elshout, Jos J.M.H.,Mutikainen, Ilpo,Fu, Wen Tian,Bouwman, Elisabeth
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Read Online
- Hybrid bis-histidine phenanthroline-based ligands to lessen aβ-bound cu ros production: An illustration of cu(i) significance
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We here report the synthesis of three new hybrid ligands built around the phenanthroline scaffold and encompassing two histidine-like moieties: phenHH, phenHGH and H’phenH’, where H correspond to histidine and H’ to histamine. These ligands were designed to capture Cu(I/II) from the amyloid-β peptide and to prevent the formation of reactive oxygen species produced by amyloid-β bound copper in presence of physiological reductant (e.g., ascorbate) and dioxygen. The amyloid-β peptide is a well-known key player in Alzheimer’s disease, a debilitating and devasting neurological disorder the mankind has to fight against. The Cu-Aβ complex does participate in the oxidative stress observed in the disease, due to the redox ability of the Cu(I/II) ions. The complete characterization of the copper complexes made with phenHH, phenHGH and H’phenH’ is reported, along with the ability of ligands to remove Cu from Aβ, and to prevent the formation of reactive oxygen species catalyzed by Cu and Cu-Aβ, including in presence of zinc, the second metal ions important in the etiology of Alzheimer’s disease. The importance of the reduced state of copper, Cu(I), in the prevention and arrest of ROS is mechanistically described with the help of cyclic voltammetry experiments.
- Drommi, Marielle,Esmieu, Charlène,Hureau, Christelle,Rulmont, Clément
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supporting information
(2021/12/24)
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- From Pyridine- N-oxides to 2-Functionalized Pyridines through Pyridyl Phosphonium Salts: An Umpolung Strategy
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The reactions of pyridine-N-oxides with Ph3P under the developed conditions provide an unprecedented route to (pyridine-2-yl)phosphonium salts. Upon activation with DABCO, these salts readily serve as functionalized 2-pyridyl nucleophile equivalents. This umpolung strategy allows for the selective C2 functionalization of the pyridine ring with electrophiles, avoiding the generation and use of unstable organometallic reagents. The protocol operates at ambient temperature and tolerates sensitive functional groups, enabling the synthesis of otherwise challenging compounds.
- Bugaenko, Dmitry I.,Yurovskaya, Marina A.,Karchava, Alexander V.
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supporting information
p. 6099 - 6104
(2021/08/03)
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- A single iron porphyrin shows ph dependent switch between "push" and "pull" effects in electrochemical oxygen reduction
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The "push-pull"effects associated with heme enzymes manifest themselves through highly evolved distal amino acid environments and axial ligands to the heme. These conserved residues enhance their reactivities by orders of magnitude relative to small molecules that mimic the primary coordination. An instance of a mononuclear iron porphyrin with covalently attached pendent phenanthroline groups is reported which exhibit reactivity indicating a pH dependent "push"to "pull"transition in the same molecule. The pendant phenanthroline residues provide proton transfer pathways into the iron site, ensuring selective 4e-/4H+ reduction of O2 to water. The protonation of these residues at lower pH mimics the pull effect of peroxidases, and a coordination of an axial hydroxide ligand at high pH emulates the push effect of P450 monooxygenases. Both effects enhance the rate of O2 reduction by orders of magnitude over its value at neutral pH while maintaining exclusive selectivity for 4e-/4H+ oxygen reduction reaction.
- Bhunia, Sarmistha,Dey, Abhishek,Dey, Somdatta Ghosh,Mukherjee, Sudipta,Nayek, Abhijit
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p. 14564 - 14576
(2020/11/02)
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- Reaction of Pyridine-N-Oxides with Tertiary sp2-N-Nucleophiles: An Efficient Synthesis of Precursors for N-(Pyrid-2-yl)-Substituted N-Heterocyclic Carbenes
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N-(Pyrid-2-yl)-substituted azolium and pyridinium salts, precursors for hybrid NHC-containing ligands, were obtained with excellent regioselectivity, employing a deoxygenative CH-functionalization of pyridine-N-oxides with substituted imidazoles, thiazoles, and pyridine. Unlike the traditional SNAr-based methods, this approach provides high yields for substrates bearing substituents of different electronic nature. The utility of azolium and pyridinium salts thus prepared was also highlighted by the synthesis of pyridyl-substituted imidazolyl-2-thione, benzodiazepine as well as 2-aminopyridines.
- Bugaenko, Dmitry I.,Karchava, Alexander V.,Yurovskaya, Marina A.
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supporting information
p. 5777 - 5782
(2020/12/01)
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- Copper-Catalyzed Regioselective C-H Amination of Phenol Derivatives with Assistance of Phenanthroline-Based Bidentate Auxiliary
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A copper-catalyzed regioselective direct amination of phenol derivatives with diarylamines via phenanthroline-based bidentate auxiliary-directed C-H cleavage has been developed. This reaction proceeds smoothly with only a copper salt and air as a terminal oxidant to produce the corresponding o-aminophenols in good yields. Moreover, the directing group can be easily attached, detached, and recycled. Additionally, preliminary computational studies of the reaction with DFT have also been performed.
- Takamatsu, Kazutaka,Hayashi, Yoshihiro,Kawauchi, Susumu,Hirano, Koji,Miura, Masahiro
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p. 5336 - 5344
(2019/06/13)
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- NNB-type tridentate boryl ligands enabling a highly active iridium catalyst for C–H borylation
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Boryl ligands play a very important role in catalysis because of their very high electron-donating property. In this paper, NNB-type boryl anions were designed as tridentate ligands to promote aryl C–H borylation. In combination with [IrCl(COD)]2/su
- Ding, Siyi,Wang, Linghua,Miao, Zongcheng,Li, Pengfei
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- With the antibacterial activity of the substituted 2 - amido - 1, 10 - eurepium (by machine translation)
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The invention relates to a compound of formula I is shown of a substituted 2 - amido - 1, 10 - eurepium antibacterial compound or its physiologically acceptable salt and their method of preparation, also relates to a pharmaceutical composition comprising said compound. Wherein each substituent defined as stated in claims. (by machine translation)
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Paragraph 0018; 0019
(2019/06/07)
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- HYDROXYPHENYL PHENANTHROLINES AS POLYMERIZABLE BLOCKERS OF HIGH ENERGY LIGHT
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Described are high energy light blocking compounds and ophthalmic devices containing the compounds. In particular, described are hydroxyphenyl phenanthroline structures with polymerizable functionality that block high energy light and are visibly transpar
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Paragraph 0288; 0293
(2019/01/15)
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- Tridentate Directing Groups Stabilize 6-Membered Palladacycles in Catalytic Alkene Hydrofunctionalization
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Removable tridentate directing groups inspired by pincer ligands have been designed to stabilize otherwise kinetically and thermodynamically disfavored 6-membered alkyl palladacycle intermediates. This family of directing groups enables regioselective remote hydrocarbofunctionalization of several synthetically useful alkene-containing substrate classes, including 4-pentenoic acids, allylic alcohols, homoallyl amines, and bis-homoallylamines, under Pd(II) catalysis. In conjunction with previous findings, we demonstrate regiodivergent hydrofunctionalization of 3-butenoic acid derivatives to afford either Markovnikov or anti-Markovnikov addition products depending on directing group choice. Preliminary mechanistic and computational data are presented to support the proposed catalytic cycle.
- O'Duill, Miriam L.,Matsuura, Rei,Wang, Yanyan,Turnbull, Joshua L.,Gurak, John A.,Gao, De-Wei,Lu, Gang,Liu, Peng,Engle, Keary M.
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supporting information
p. 15576 - 15579
(2017/11/14)
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- Bio-inspired Herringbone Foldamers: Strategy for Changing the Structure of Helices
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Cyclic oligomers of azole peptides were isolated from a multitude of marine organisms and were used for a large number of molecular machines. As shown previously, oligomers derived from achiral imidazole amino acids fold into canonical helices. Here we show that a minor change, the introduction of a methyl group in the δ position, results in a significant change in the secondary structure of the corresponding oligomers. Instead of a canonical helix, a noncanonical herringbone helix is formed. In the latter, the slope along the helix changes its sign at least twice per turn. This strategy allows a remarkable change of the secondary structure via a small modification. By means of enantiomerically pure amino acids, we were able to control, for the first time, both the helicity of the helix and the form of the herringbone. The investigation of the underlying herringbone basic element and its folding to a noncanonical helix were conducted by NMR and CD spectroscopy, as well as by X-ray crystallography and quantum chemical calculations.
- Adam, Abdulselam,Haberhauer, Gebhard,W?lper, Christoph
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p. 4203 - 4215
(2017/04/28)
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- Metal-free phosphonation of heteroarene N-oxides with trialkyl phosphite at room temperature
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A new protocol is described for the conversion of heteroarene N-oxides to heteroarylphosphonates through in situ activation with bromotrichloromethane. The N-oxides of isoquinoline, quinoline, quinoxaline and 1,10-phenanthroline were fast transformed into the corresponding heteroarylphosphonates in up to 92% yield under mild conditions in the absence of solvent and metal catalysts. The good functional group tolerance, low cost, feasibility of scale up, and wide availability of reagents make this method a prominent complement to the Hirao coupling.
- Chen, Ming-Tao,You, Xia,Bai, Li-Gang,Luo, Qun-Li
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supporting information
p. 3165 - 3169
(2017/04/21)
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- A 1,10-phenanthrene rowling-N-Monoxide derivatives ligand and its application
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The invention relates to a 1,10-Phenanthroline monohydrate-dual N-monoxide derivative ligand. The derivative ligand has a structural formula as follows: FORMULA, wherein R1 and R8 are selected from hydrogen, halogen, hydroxyl, C1-C7 alkoxyl, straight-chain saturated or unsaturated C1-C6 alkyl, or branched-chain saturated or unsaturated C1-C6 alkyl; R2 to R7 are selected from hydrogen, halogen, hydroxyl, C1-C8 alkoxyl, straight-chain saturated or unsaturated C1-C6 alkyl, or branched-chain saturated or unsaturated C1-C6 alkyl, C3-C7 ring hydroxyl, benzyl, aryl or 5-7 membered heterocyclic ring. Hetero atoms (such as O or N) are contained in the ligand disclosed by the invention, and a transitional six-membered ring is formed through coordination with copper ions, so that aryl iodide, aryl bromide or aryl chloride is promoted to carry out a C-N coupling reaction with aliphatic amine or secondary aliphatic cyclammonium or aliphatic acid or nitrogen-containing heterocyclic compounds at room temperature.
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Paragraph 0025-0027
(2016/11/21)
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- Novel method for synthesizing 1,10-phenanthroline-2-amine
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The invention relates to a novel method for synthesizing 1,10-phenanthroline-2-amine. 1,10-phenanthroline is subjected to an amino oxidation reaction, a substitution reaction and an elimination reaction on an aromatic nucleus to be synthesized into 1,10-phenanthroine-2-amine. According to the novel method, the defects of the prior art are overcome, and usage of dangerous goods such as phosphorus oxychloride is avoided; meanwhile, high temperature and high pressure are not needed in the reaction conditions, the reaction conditions are mild, the adopted raw materials are easy to obtain, the total yield is high, the cost is low, the method is safe and friendly to the environment, and the good industrial application prospect is achieved.
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Paragraph 0018; 0019; 0020
(2017/06/06)
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- Metal-Free, Phosphonium Salt-Mediated Sulfoximination of Azine N-Oxides: Approach for the Synthesis of N-Azine Sulfoximines
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Herein, we report a simple and metal-free method for the synthesis of N-azine sulfoximines by the nucleophilic substitution of azine N-oxides with NH-sulfoximines. The present method works at room temperature with wide functional group compatibility and gives several unprecedented N-azine sulfoximines. The reaction conditions were also found suitable with enantiopure substrates and furnished products without any racemization. It also finds an application in the sulfoximination of azine-based functional molecules such as 2,2′-bipyridine, 1,10-phenanthroline, and quinine.
- Aithagani, Sravan Kumar,Kumar, Mukesh,Yadav, Mahipal,Vishwakarma, Ram A.,Singh, Parvinder Pal
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p. 5886 - 5894
(2016/07/23)
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- O-phenanthrene pyrrodiazoles rare earth complex and its preparation method
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The invention provides a novel o-phenanthroline triazole rare earth complex LnL3 and a preparation method thereof. The structural formula of the o-phenanthroline triazole rare earth complex LnL3 is shown in formula 1, wherein R1 is selected from amino, alkyl or aromatic hydrocarbon groups, R2 is selected from amino, alkyl or aromatic hydrocarbon groups, R3 is selected from amino, halogen, alkyl, halogenated alkyl or aromatic hydrocarbon groups, and a central rare earth ion Ln is selected from any one of yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. The o-phenanthroline triazole rare earth complex LnL3 disclosed by the invention takes an o-phenanthroline triazole trident compound as a single ligand, and satisfies the ligand saturation, and a situation that a charge balance is electrically neutral is realized between triazole groups in the complex as anions and central rare earth metal cations. The rare earth complex disclosed by the invention is high in thermal stability, and is suitable for device preparation implemented by using an evaporation film-forming process or a solution film-forming process. The preparation method is high in yield, good in product purity, short in reaction time and simple in operation, and the cost is greatly reduced.
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Paragraph 0040-0043
(2016/10/08)
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- Nitrogen-containing tooth heterocyclic ring substituted tetrazole rare earth complex and its preparation method
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The invention provides a nitrogen-containing double-tooth heterocyclic ring substituted tetrazole type rare-earth complex LnL3 expressed by the formula I, wherein Ar is a nitrogen-containing double-tooth heterocyclic ring; the center rare-earth ion Ln is any one of yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium. The preparation method of the nitrogen-containing double-tooth heterocyclic ring substituted tetrazole type rare-earth complex LnL3 is characterized in that a nitrogen-containing double-tooth heterocyclic ring substituted tetrazole type three-tooth compound, namely a dipyridyl tetrazole type three-tooth compound or phenanthroline tetrazole type three-tooth compound, is taken as a single ligand, and simultaneously, coordination saturation is satisfied, and the tetrazole group in the complex serves as negative irons to realize electrically neutral charge balance together with center rare-earth metal cations. The obtained rare-earth complex is high in thermal stability, can be prepared into a device through an evaporation film-forming process or a solution film-forming process. Besides, the preparation method has the advantages of high yield, of the product has high purity, reaction time is short and operation is simple; and as a result, the cost is greatly reduced.
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Paragraph 0106-0108
(2016/11/24)
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- Insights into the mechanistic and synthetic aspects of the Mo/P-catalyzed oxidation of N-heterocycles
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A Mo/P catalytic system for an efficient gram-scale oxidation of a variety of nitrogen heterocycles to N-oxides with hydrogen peroxide as terminal oxidant has been investigated. Combined spectroscopic and crystallographic studies point to the tetranuclear Mo4P peroxo complex as one of the active catalytic species present in the solution. Based on this finding an optimized catalytic system has been developed. The utility and chemoselectivity of the catalytic system has been demonstrated by the synthesis of over 20 heterocyclic N-oxides.
- Larionov, Oleg V.,Stephens, David,Mfuh, Adelphe M.,Arman, Hadi D.,Naumova, Anastasia S.,Chavez, Gabriel,Skenderi, Behije
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p. 3026 - 3036
(2014/05/06)
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- Monitoring helical twists and effective molarities in dinuclear triple-stranded lanthanide helicates
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The replacement of terminal benzimidazole-pyridine binding units in the neutral di-tridentate segmental ligand L1 with phenanthroline in L10 reduces the number of torsional degrees of freedom by two units. Reactions of these ligands with trivalent europium or lutetium cations yield structurally similar self-assembled dinuclear triple-stranded [Ln2(Lk)3] 6+ complexes, thus demonstrating that the increased rigidity of the strand in L10 is compatible with its helical twist. With the larger lanthanum cations, the metallic coordination spheres are completed with two terminal axial triflate counter-anions to give [La2(L10)3(CF 3SO3)2]4+. Thermodynamic investigations in acetonitrile confirm the minor constraints produced by the planar phenanthroline unit in L10 leading to comparable effective molarities EMEu,L1 ≈ EMEu,L10 = 10 -3.9(4) M with mid-range EuIII cations. The striking minute effective molarities EMLn,Ln-2H ≈ 10-6-10-9 M obtained upon the replacement of terminal phenanthrolines with structurally analogous fused hydroxyquinolines in L9 can be thus unambiguously assigned to solvation effects, a new tool for controlling complexity in metal-induced self-assembly processes.
- Ryan, Patrick E.,Guenee, Laure,Piguet, Claude
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p. 11047 - 11055
(2013/08/23)
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- Substituted phenanthrolines as antennae in luminescent EuIII complexes
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Eight novel europium(III)-based coordination compounds with 1,10-phenanthroline (phen) ligands with a chloro, methoxy, ethoxy, cyano, carboxylic acid, methyl carboxylate, ethyl carboxylate, and amino substituent on the 2-position have been prepared in yields ranging from 43 to 89 %. Additionally, one lanthanum(III) coordination compound of 2-amino-1,10- phenanthroline has been isolated. All compounds have the general formula [Ln(L)2(NO3)3], except for the compound with the carboxylate ligand, which has the formula [Eu(O2Cphen) 3]. Three of the EuIII complexes as well as the La III compound crystal structures have been determined, all of which show similar N4O6 coordination spheres for the Ln III ion. Seven compounds exhibit bright luminescence that is characteristic of EuIII upon irradiation with near-UV radiation, thus indicating efficient ligand-to-metal energy transfer. The complex with 2-amino-1,10-phenanthroline is nonluminescent. The solid-state photoluminescent quantum yields range from 10 to 79 %, and the luminescence lifetimes vary from 0.43 to 1.57 ms. Analysis of the spectral intensities with the Judd-Ofelt theory shows a significant contribution of nonradiative processes that quench the luminescence of the 5D0 level on EuIII. Eight new EuIII complexes with 1,10-phenanthroline ligands substituted on the 2-position have been prepared, analyzed, and the photoluminescence properties studied. The complex with the 2-chloro substituent exhibits bright photoluminescence with a high quantum yield of 78 %. The complex with the 2-amino substituent is nonluminescent. Copyright
- Akerboom, Sebastiaan,Van Den Elshout, Jos J. M. H.,Mutikainen, Ilpo,Siegler, Maxime A.,Fu, Wen Tian,Bouwman, Elisabeth
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supporting information
p. 6137 - 6146
(2014/01/06)
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- Highly effective recognition of carbohydrates by phenanthroline-based receptors: α- versus β-anomer binding preference
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1H NMR spectroscopic titrations in competitive and non-competitive media, as well as binding studies in two-phase systems, such as phase transfer of sugars from aqueous into organic solvents and dissolution of solid carbohydrates in apolar medi
- Mazik, Monika,Hartmann, Andre,Jones, Peter G.
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scheme or table
p. 9147 - 9159
(2010/04/05)
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- Phenanthroline unit as a building block for carbohydrate receptors
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(Figure Presented) An acyclic receptor 1, containing phenanthroline- and aminopyridine-based recognition sites, has been established as a powerful carbohydrate receptor. Compared to the previously described acyclic receptors, compound 1 shows significantl
- Mazik, Monika,Hartmann, Andre
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p. 7444 - 7450
(2008/12/22)
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- Phenanthroline-derived ratiometric chemosensor for ureas
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The syntheses of 1,10-phenanthroline fluorophore-based chemosensor 7 and its truncated analog 9 are reported. Interactions of these compounds with urea, thiourea, 1,3-dimethylurea, tetrahydropyrimidin-2(lH)-one, imidazolidin-2-one, and selected uronium sa
- Engel, Yoni,Dahan, Adi,Rozenshine-Kemelmakher, Emily,Gozin, Michael
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p. 2318 - 2328
(2007/10/03)
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- Dipyridine-based compound and the use thereof
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The present invention discloses a dipyridine-based compound which can be used as electron-transporting and/or hole blocking material or phosphorous host in organic electroluminescence devices is disclosed. The mentioned dipyridine-based compound is represented by the following formula: wherein R1 and R2 are identical or different, and R1 and R2 are independently selected from the group consisting of: hydrogen atom, aryl moiety, hetero cycle, multiple fused ring, multiple fused ring with hetero atom(s); A is selected from the following group: wherein R3 and R4 are identical or different, R5 and R6 are identical or different, R7 and R8 are identical or different, R3, R4, R7, R8 are independently selected from the group consisting of: alkyl moiety and aryl moiety, and R5, R6 are independently selected from the group consisting of: alkyl moiety, aryl moiety and arylamine moiety.
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Page/Page column 20
(2008/06/13)
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- A simple and efficient method for the preparation of N- heteroaromatic N-oxides
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Urea-hydrogen peroxide/formic acid system has shown utility for mild and safe N-oxidation of N-heteroaromatic compounds.
- Balicki, Roman,Golinski, Jerzy
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p. 1529 - 1534
(2007/10/03)
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- At last, 1,10-phenanthroline-N,N-dioxide, a new type of helicene, has been synthesized using HOF · CH3CN
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For more than 50 years the synthesis of 1,10-phenanthroline-N,N'-dioxide (2) has been sought. The reason for the failure of all the earlier attempts is that the limited space in the bay area of the starting material 1,10- phenanthroline (1) cannot accommodate two oxygen atoms. The oxidation has now been achieved with the oxygen-transfer agent HOF. CH3CN, and X-ray studies have revealed that the product is not planar but is a new type of helicene - in this way the 'space problem' for the two oxygen atoms has been solved.
- Rozen, Shlomo,Dayan, Sharon
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p. 3472 - 3473
(2007/10/03)
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- On the chlorine addition to the C(5)-C(6) bridge and the N-oxidation of 1,10-phenanthroline
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It was found that under the influence of aqueous hypochlorite 1,10-phenanthroline (1) is initially transformed into 5,6-dichloro-5,6-dihydro-1,10-phenanthroline (2) and 5-chloro-6-hydroxy-5,6-dihydro-1,10-phenanthroline (8). The latter readily undergoes subsequent transformations either into a mixture of 5,5-dichloro-6-oxo-5,6-dihydro-1,10-phenanthroline (4) and 5,6-dioxo-5,6-dihydro-1,10-phenanthroline (5) or into the known 5,6-epoxy-1,10-phenanthroline (3) depending on the acidic or alkaline conditions, respectively. In contrast to the flat molecule of the starting 1, that of the dichloro derivative (2) being twisted at the central bond of the bipyridine system can be easily N-oxidized to di-N-oxide (11). Both 2 and its di-N-oxide (11) in the presence of sodium isopropoxide at 0°C freely lost hydrogen chloride and returned to the fully aromatic system of 5-chloro-1,10-phenanthroline (9) and its di-N-oxide (13), respectively.
- Antkowiak, Roza,Antkowiak, Wieslaw Z.
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p. 893 - 909
(2007/10/03)
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