21969-11-9Relevant articles and documents
NMR Study of Substituent Effects in 4-Substituted and 4,4'-Disubstituted Diphenyl Sulphides
Chandrasekaran, R.,Perumal, S.,Wilson, D.A.
, p. 1001 - 1006 (1987)
The proton and carbon NMR spectra of nine 4-X-diphenyl sulphides (series 1), seven 4-X-4'-NO2-diphenyl sulphides (series 2) and eight 4,4'-X2-diphenyl sulphides (series 3) have been obtained.Correlation of the 13C chemical shifts with the appropriate substituent chemical shifts (SCS) for monosubstituted benzenes (Lynch plots) show an enhancement of substituent effect at C-1 (carbon para to the substituent) in series 1 ans 2, but not in series 3.The carbons of the unsubstituted ring in series 1 also correlate with Cp-SCS, with slopes of less than unity; correlation for C-1' has a negative slope.Dual substituent parameter (DSP) correlations of the 13C chemical shifts with ?I/?oR are good to exellent for all the carbons of series 1 compounds, except those ortho to the substituent X.The carbons meta to the substituent X correlate well, but with negative values for ρI and ρR, although showing a scattered Lynch plot.Similar correlations are found with some carbon shifts in series 2, and with C-1 shifts in series 3.It is concluded that (a) reverse resonance effects are operative at the position meta to the variable substituent by virtue of the sulphur substituent ortho to that carbon; (b) there is transmission of inductive (field) and resonance effects from one aryl ring to the other, except when both rings carry substituents of the same electronic character (series 3); (c) there is some evidence for ?-polarization in the unsubstituted phenyl ring of series 1 compounds.Key words 1H NMR 13C NMR Diphenyl sulphides substituent effects
Synthesis of diaryl sulfides based on copper-doped OMS-2
Yu, Shao-Qiang,Liu, Na,Liu, Ming-Guo,Wang, Long
, p. 237 - 241 (2020/11/30)
We describe a practical protocol for efficiently preparing diaryl sulfide compounds using Cu–OMS-2 as the catalyst. Cu–OMS-2 originates from manganese oxide octahedral molecular sieves modified with copper ions and catalyzes the C–S coupling reaction of substituted thiophenols and aryl halides. This protocol has the advantages of environmental friendliness, simple operation, high yields, good tolerance of functional groups, and the Cu–OMS-2 catalytic material can be recycled several times.
Optimization of a urea-containing series of nicotinamide phosphoribosyltransferase (NAMPT) activators
Pinkerton, Anthony B.,Sessions, E. Hampton,Hershberger, Paul,Maloney, Patrick R.,Peddibhotla, Satyamaheshwar,Hopf, Meghan,Sergienko, Eduard,Ma, Chen-Ting,Smith, Layton H.,Jackson, Michael R.,Tanaka, Jun,Tsuji, Takashi,Akiu, Mayuko,Cohen, Steven E.,Nakamura, Tsuyoshi,Gardell, Stephen J.
, (2021/04/27)
NAD+ is a crucial cellular factor that plays multifaceted roles in wide ranging biological processes. Low levels of NAD+ have been linked to numerous diseases including metabolic disorders, cardiovascular disease, neurodegeneration,
Nucleophilic aromatic substitution reactions under aqueous, mild conditions using polymeric additive HPMC
Ansari, Tharique N.,Borlinghaus, Niginia,Braje, Leon H.,Braje, Wilfried M.,Handa, Sachin,Ogulu, Deborah,Wittmann, Valentin
supporting information, p. 3955 - 3962 (2021/06/17)
The use of the inexpensive, benign, and sustainable polymer, hydroxypropyl methylcellulose (HPMC), in water enables nucleophilic aromatic subsitution (SNAr) reactions between various nucleophiles and electrophiles. The mild reaction conditions facilitate a broad functional group tolerance that can be utilized for subsequent derivatization for the synthesis of pharmaceutically relevant building blocks. The use of only equimolar amounts of all reagents and water as reaction solvent reveals the greenness and sustainability of the methodology presented herein.
CuMoO4 Bimetallic Nanoparticles, An Efficient Catalyst for Room Temperature C?S Cross-Coupling of Thiols and Haloarenes
Panigrahi, Reba,Sahu, Santosh Kumar,Behera, Pradyota Kumar,Panda, Subhalaxmi,Rout, Laxmidhar
, p. 620 - 624 (2019/12/27)
CuII catalyst is less efficient at room temperature for C?S cross-coupling. C?S cross-coupling by CuII catalyst at room temperature is not reported; however, doping of copper with molybdenum metal has been realized here to be more efficient for C?S cross-coupling in comparison to general CuII catalyst. The doped catalyst CuMoO4 nanoparticle is found to be more efficient than copper. The catalyst works under mild conditions without any ligand at room temperature and is recyclable and effective for a wide range of thiols and haloarenes (ArI, ArBr, ArF) from milligram to gram scale. The copper-based bimetallic catalyst is developed and recognized for C?S cross-coupling of haloarenes with alkyl and aryl thiols.
Method for synthesizing diarylthioether compound by using manganese oxide molecular sieve doped copper catalyst
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Paragraph 0022, (2020/12/08)
The invention relates to a synthesis method of a diarylthioether compound by catalyzing with heterogeneous manganese oxide octahedral molecular sieve doped copper (Cu-OMS-2). The chemical structural formula of the compound is shown in the description, whe
An Iodide-Mediated Transition-Metal-Free Strategy towards Unsymmetrical Diaryl Sulfides via Arylhydrazines and Thiols
Asadpour, Mohammad,Azizzade, Meysam,Ghasemi, Mehran,Jafarpour, Farnaz,Rajai-Daryasarei, Saideh
supporting information, p. 727 - 734 (2020/02/25)
A mild, scalable iodine-mediated oxidative cross-coupling reaction of arylhydrazines and thiols for construction of thioethers (sulfides) in the absence of any transition metals or photocatalysts is disclosed. A variety of unsymmetrical diaryl sulfides with broad substrate scope both on thiols and hydrazines were synthesized in high yields in water at room temperature. Furthermore, to demonstrate the utility of the protocol, the above C-S bond formation was applied in the synthesis of the key structure of vortioxetine as an antidepressant drug. The gram-scale outcome also added to the potential utility of this protocol.
Homoleptic and heteroleptic Zn(ii) selone catalysts for thioetherification of aryl halides without scrubbing oxygen
Vaddamanu, Moulali,Velappan, Kavitha,Prabusankar, Ganesan
, p. 3574 - 3583 (2020/03/17)
Five new mononuclear tetra-coordinated zinc(ii) selones, [Zn(L1)2Cl2] (1), [Zn(L1)2Br2] (2), [{Zn(L2)4}{BF4}2] (3), [{Zn(L2)4}{ClO4}2] (4), and [Zn(L2)2Br2] (5), have been isolated from a one-pot reaction between the corresponding zinc(ii) salt and selone ligand, 1-methyl 3-naphthylmethylimidazoline-2-selone (L1) or 1-isopropyl 3-methylimidazoline-2-selone (L2). All these complexes were characterized by CHN analysis, FT-IR, NMR studies, and single-crystal X-ray crystallography techniques. The Zn(ii) center in 1-5 exhibits a distorted tetrahedral geometry. Besides, 1-5 were employed as catalysts in the thioetherification of aryl halides. The first zinc(ii) catalyst-mediated thioetherification of aryl halides without scrubbing oxygen was demonstrated. Catalysts 1-5 are highly active towards the cross-coupling reaction between aryl halides and thiophenols. The catalytic ability of 1-5 was explored in THF, toluene, and CH3CN solvents with different bases such as K2CO3, Cs2CO3, and NaOtBu. Interestingly, the zinc(ii) center attached to two selone ligands is much more catalytically active than that attached to four selone ligands.
Highly active mesoionic chalcogenone zinc(II) derivatives for C-S cross-coupling reactions
Vaddamanu, Moulali,Prabusankar, Ganesan,Velappan, Kavitha
, p. 129 - 140 (2019/12/26)
The first mesoionic heavier chalcogenones, L1-L3 [L1 = 1-(2-mesitylene)-3-methyl-4-phenyltriazolin-5-selone; L2 = 1-(2-mesitylene)-3-methyl-4-phenyltriazolin-5-thione; L3 = 1-(benzyl)-2-3(methyl)-4-phenyltriazolin-5-selone], were isolated and characterised. Density functional theory was used to obtain insights into the σ donor and π accepting nature of mesoionic chalcogenones. Using these new ligands, a series of the first zinc(ii) mesoionic chalcogenone complexes were isolated. Three mono nuclear zinc(ii) chalcogenone complexes, [(L1)Zn(Cl)2(HOMe)] (1), [(L2)Zn(Cl)2(HOMe)] (3) and [(L2)Zn(Br)2(HOMe)] (4), and two dinuclear zinc complexes, [(L1)Zn(Br)(μ2-Br)]2 (2) and [(L3)Zn(Br)(μ2-Br)]2 (5), containing mesoionic thione and selone ligands were synthesized and characterised. These new complexes 1-5 represent the first structurally characterized mesoionic chalcogenone supported metal derivatives. Furthermore, all zinc complexes were characterized by thermogravimetric analysis and UV-vis spectroscopy. The solid-state structures of all zinc complexes were determined by single-crystal X-ray diffraction. The catalytic activities of the zinc(ii) complexes in thioetherification reactions were investigated without scrubbing of oxygen. The scope of the catalytic reactions was explored with a wide range of thiophenols and aryl halides. The diaryl thioethers were obtained in very good yield under mild conditions. The present protocol furnishes a synthetic route for the C-S cross-coupling of thiophenols and aryl halides without scrubbing oxygen and moisture.
Copper(II)-faciliated synthesis of substituted thioethers and 5-substituted 1H-tetrazoles: Experimental and theoretical studies
Layek, Samaresh,Agrahari, Bhumika,Dey, Shuvankar,Ganguly, Rakesh,Pathak, Devendra D.
, p. 194 - 206 (2019/06/24)
Benzoylhydrazine based Schiff base-ligated two new copper(II) complexes, [Cu(L1)2] (1) and [Cu(L2)2] (2) were synthesized by the reaction of Cu(CH3COO)2·H2O with respective Schiff base ligand 1-[(4-nitrophenyl)ethylidene] benzohydrazide (HL1) or 1-[(4-methoxyphenyl)ethylidene] benzohydrazide (HL2). Both complexes were isolated as greenish solid and fully characterized by elemental analysis, FT-IR, EPR, thermo-gravimetric (TG) analysis and Cyclic Voltammetry. The molecular structures of both complexes have also been determined by single crystal X-ray crystallography, which confirmed the coordination of Schiff base ligands through N, O donor atoms and distorted square planar geometry around the Cu(II) ion. Both complexes were found to be good homogeneous catalysts for the synthesis of a wide range of substituted thioethers and 5-substituted 1H-tetrazoles in 92% and 93% yield, respectively, at a low catalyst loading (0.5 mol%). The bond angles and distances, as discerned from the DFT calculations, commusurated with the experimental findings. The energy difference between the HOMO and the LUMO, calculated from DFT studies, was found to be 5.645 eV and 6.459 eV for complex 1 and complex 2, respectively. These results are in harmony with the observed higher catalytic activity of complex 1.
