- Solid Versus Solution Spin Crossover and the Importance of theFe-N - (X) Angle
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A new family of mononuclear [FeII(Rdpt)2(NCE)2] complexes (E = S, Se, or BH3) is formed by 1:2 reaction of [FeII(pyridine)4(NCE)2] with the monotopic pyridyl triazole ligand 4-(4-methylphenyl)-3-(2-pyridinyl)-5-phenyl-4H-1,2,4-triazole (tolpyph). The three complexes are obtained as six different solvatomorphs: [FeII(tolpyph)2(NCS)2]·H2O (1·H2O), 1·1.5CH3OH·0.5H2O, [FeII(tolpyph)2(NCSe)2] (2), 2·1.5H2O, [FeII(tolpyph)2(NCBH3)2] (3), and 3·H2O. Single-crystal X-ray diffraction reveals that 1·1.5CH3OH·0.5H2O and 2 are high-spin (HS) at 100 K, while 3 is low-spin (LS) at 100 K and HS at 373 K. Compound 3 is the first structurally characterized example of an [FeII(Rdpt)2(NCE)2]-type complex with NCBH3 co-ligand: the crystal packing is dominated by aromatic stacking interactions. Solid-state magnetic measurements show that 1·H2O and 2·1.5H2O remain HS down to 50 K, whereas 3·H2O undergoes spin crossover (SCO) with a T1/2 of 309 K, slightly above room temperature. A literature survey of analogous trans-[FeII(Rdpt)2(NCX)2]-type complexes (53 distinct crystal structures) shows that for the complexes that are SCO active in the solid state the Fe-N - C(X) angle is usually close to straight, 162-178°, whereas it is usually lower, 142-159°, for the complexes that remain HS. UV-vis studies in CHCl3 solution show that in each case the use of a 6:1 ratio of tolpyph/Fe(II) is required to ensure the iron(II) is present in solution as [FeII(tolpyph)2(NCE)2]. Interestingly, using this ratio, all three compounds are SCO-active in CDCl3 solution-in dramatic contrast to the solid-state findings. Specifically, while compounds 1 and 2 are not SCO-active in the solid state (they remain HS), they undergo gradual SCO in CDCl3 solution, with T1/2 values of 290 and 310 K, respectively. In CDCl3 solution, compound 3 has a T1/2 value of 288 K, which is 21 K lower than in the solid state. These results highlight the differences between solid state (ligand field; crystal packing) and solution (ligand field; solvation) effects on SCO, with the latter studies revealing roomerature SCO for all three of these complexes.
- Rodríguez-Jiménez, Santiago,Brooker, Sally
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Read Online
- Visible-Light Carbon Nitride-Catalyzed Aerobic Cyclization of Thiobenzanilides under Ambient Air Conditions
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A metal-free heterogeneous photocatalysis has been developed for the synthesis of benzothiazoles via intramolecular C-H functionalization/C-S bond formation of thiobenzanilides by inexpensive graphitic carbon nitride (g-C3N4) under visible-light irradiation. This reaction provides access to a broad range of 2-substituted benzothiazoles in high yields under an air atmosphere at room temperature without addition of a strong base or organic oxidizing reagents. In addition, the catalyst was found to be stable and reusable after five reaction cycles.
- Bai, Jin,Yan, Sijia,Zhang, Zhuxia,Guo, Zhen,Zhou, Cong-Ying
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p. 4843 - 4848
(2021/06/28)
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- A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson's reagent
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After completing the thio-substitution with Lawesson's reagent, ethanol was found to be effective in the decomposition of the inherent stoichiometric six-membered-ring byproduct from the Lawesson's reagent to a highly polarized diethyl thiophosphonate. The treatment significantly simplified the following chromatography purification of the desired thioamide in a small scale preparation. As scaling up the preparation of two pincer-type thioamides, we have successfully developed a convenient process with ethylene glycol to replace ethanol during the workup, including a traditional phase separation, extraction, and recrystallization. The newly developed chromatography-free procedure did not generate P-containing aqueous waste, and only organic effluents were discharged. It is believed that the optimized procedure offers the great opportunity of applying the Lawesson's reagent for various thio-substitution reactions on a large scale.
- Wu, Ke,Ling, Yichen,Ding, An,Jin, Liqun,Sun, Nan,Hu, Baoxiang,Shen, Zhenlu,Hu, Xinquan
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p. 805 - 812
(2021/05/03)
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- Mild and Chemoselective Thioacylation of Amines Enabled by the Nucleophilic Activation of Elemental Sulfur
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A mild and chemoselective method for the thioacylation of amines using α-keto acids and elemental sulfur has been developed. The key to the success of this transformation is the nucleophilic activation of elemental sulfur by thiols such as 1-dodecanethiol
- Saito, Masato,Murakami, Sho,Nanjo, Takeshi,Kobayashi, Yusuke,Takemoto, Yoshiji
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supporting information
p. 8130 - 8135
(2020/05/20)
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- Extension of Azine-Triazole Synthesis to Azole-Triazoles Reduces Ligand Field, Leading to Spin Crossover in Tris-L Fe(II)
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The first examples of azole-Triazole Rat ligands, bidentate L4NMeIm(3-(1-methyl-1H-imidazol-4-yl)-5-phenyl-4-(p-Tolyl)-4H-1,2,4-Triazole) and L4SIm (4-(5-phenyl-4-(p-Tolyl)-4H-1,2,4-Triazol-3-yl)thiazole), have been prepared, by extension of the general synthesis used to access many examples of azine-Triazoles. The tris-L FeII complexes of the azine-Triazoles are consistently low spin (LS). As intended, these new azole-Triazole ligands provide lower field strengths, resulting in high-spin (HS) [FeII(L4NMeIm)3](BF4)2 (1·4H2O) and spin crossover (SCO) active [FeII(L4SIm)3](BF4)2 (2·0.5H2O). Single-crystal structure determinations revealed that at 100 K 1·solvents is HS whereas 2·solvents is LS. Solid-state variable temperature magnetic studies of air-dried crystals showed that the methylimidazole-Triazole complex 1·4H2O remains HS while the thiazole-Triazole complex 2·0.5H2O undergoes a two-step gradual SCO (T1/2 approximately 275 and 350 K). Variable-Temperature Evans method NMR studies of 2, in five different solvents (CD3NO2, CD3CN, CD3COCD3, CD2Cl2, and CDCl3) gave T1/2 values in a relatively narrow range, 214-259 K. These T1/2 values did not correlate with the solvent polarity index P′ (R2 = 0.25) but did correlate with the solvent basicity parameter SB (R2 = 0.90). Variable-Temperature UV-vis studies on a golden yellow CH3CN solution of 2, with monitoring of the d-d transition at 530 nm (? = 39 L mol-1 cm-1 at 293 K) while the solution was heated from 253 to 303 K, showed that the high-spin fraction increased from 0.51 to 0.77. Cyclic voltammetry studies in CH3CN revealed a Fe(III)/Fe(II) redox process that was reversible for 1 and irreversible for 2, with significant tuning of the Epa value: The methylimidazole-Triazole complex 1 is significantly easier to oxidize (0.46 V) than the thiazole-Triazole complex 2 (0.68 V; both vs 0.01 M Ag/AgNO3).
- Brooker, Sally,Singh, Sandhya
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- Iron-Catalyzed Regioselective Synthesis of 2-Arylbenzoxazoles and 2-Arylbenzothiazoles via Alternative Reaction Pathways
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A one-pot regioselective method for the preparation of 2-arylbenzoxazoles from N-arylbenzamides has been developed using iron(III)-catalyzed bromination of the aryl ring, followed by copper(I)-catalyzed O-cyclization with the benzamide side chain. In contrast, reaction of N-arylthiobenzamides with N-bromosuccinimide and iron triflimide led directly to the isolation of the corresponding 2-arylbenzothiazoles via intramolecular C–S bond formation. Mechanistic and control experiments suggest that in this case, bromination occurs at the sulfur atom, resulting in a reactive intermediate that can undergo electrophilic aromatic substitution and S-cyclization. The scope of both processes was explored yielding a range of structural analogues, including a pharmaceutically active compound for the treatment of Duchenne muscular dystrophy and an affinity agent of the amyloid-beta protein in Alzheimer's disease.
- Henry, Martyn C.,Abbinante, Vincenzo Mirco,Sutherland, Andrew
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supporting information
p. 2819 - 2826
(2020/04/10)
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- Functionalization of activated methylene C-H bonds with nitroarenes and sulfur for the synthesis of thioamides
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We report a method to obtain arylthioamides by the functionalization of sp3 C-H bonds in phenylacetic acids and benzyl alcohols. Reactions proceeded without the use of any solvents and were compatible with many functionalities and heterocycles. These conditions allow for a rapid synthesis of thioamides from simple, commercial substrates.
- Do, Nhan T.,Tran, Khoa M.,Phan, Hao T.,To, Tuong A.,Nguyen, Tung T.,Phan, Nam T. S.
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supporting information
p. 8987 - 8991
(2019/10/28)
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- Transition metal-free α-Csp3-H oxidative sulfuration of benzyl thiosulfates with anilines to form N-aryl thioamides
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A metal-free approach to N-aryl thioamides from Bunte salts and anilines in DMSO has been developed. This method tolerated a wide range of functional groups on the aromatic ring, providing an ideal way to N-aryl thioamides in good to excellent yields from cheap and easily available starting materials. A plausible mechanism was also proposed based on the X-ray single crystal diffraction, NMR and MS analyses of DMSO-concerning intermediates.
- Qiao, Mengjun,Zhang, Jinli,Chen, Ling,Zhou, Fengyi,Zhang, Yali,Zhou, Lingfei,Wu, Yangjie
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supporting information
p. 3790 - 3796
(2019/04/17)
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- Iron-Promoted Three-Component 2-Substituted Benzothiazole Formation via Nitroarene ortho-C-H Sulfuration with Elemental Sulfur
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A three-component procedure for the preparation of 2-substituted benzothiazoles from nitroarenes, alcohols, and sulfur powder is described. The reaction showed a good functional group tolerance to provide the heterocyclic products in moderate to good yields. The sequential assembly involving nitro reduction, C-N condensation, and C-S bond formation has been realized in one pot.
- Xing, Qiaoyan,Ma, Yanfeng,Xie, Hao,Xiao, Fuhong,Zhang, Feng,Deng, Guo-Jun
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supporting information
p. 1238 - 1246
(2019/01/21)
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- Exogenous Photosensitizer-, Metal-, and Base-Free Visible-Light-Promoted C-H Thiolation via Reverse Hydrogen Atom Transfer
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Visible-light-driven, intramolecular C(sp2)-H thiolation has been achieved without addition of a photosensitizer, metal catalyst, or base. This reaction induces the cyclization of thiobenzanilides to benzothiazoles. The substrate absorbs visible light, and its excited state undergoes a reverse hydrogen-atom transfer (RHAT) with 2,2,6,6-tetramethylpiperidine N-oxyl to form a sulfur radical. The addition of the sulfur radical to the benzene ring gives an aryl radical, which then rearomatizes to benzothiazole via RHAT.
- Xu, Ze-Ming,Li, Hong-Xi,Young, David James,Zhu, Da-Liang,Li, Hai-Yan,Lang, Jian-Ping
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p. 237 - 241
(2019/01/10)
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- Solvent Polarity Predictably Tunes Spin Crossover T1/2 in Isomeric Iron(II) Pyrimidine Triazoles
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Two isomeric pyrimidine-based Rdpt-type triazole ligands were made: 4-(4-methylphenyl)-3-(2-pyrimidyl)-5-phenyl-4H-1,2,4-triazole (L2pyrimidine) and 4-(4-methylphenyl)-3-(4-pyrimidyl)-5-phenyl-4H-1,2,4-triazole (L4pyrimidine). When reacted with [FeII(pyridine)4(NCE)2], where E = S, Se, or BH3, two families of mononuclear iron(II) complexes are obtained, including six solvatomorphs, giving a total of 12 compounds: [FeII(L2pyrimidine)2(NCS)2] (1), [FeII(L2pyrimidine)2(NCSe)2] (2), 2·1.5H2O, [FeII(L2pyrimidine)2(NCBH3)2]·2CHCl3 (3·2CHCl3), 3 and 3·2H2O, [FeII(L4pyrimidine)2(NCS)2] (4), 4·H2O, [FeII(L4pyrimidine)2(NCSe)2] (5), 5·2CH3OH, 5·1.5H2O, and [FeII(L4pyrimidine)2(NCBH3)2]·2.5H2O (6·2.5H2O). Single-crystal X-ray diffraction reveals that the N6-coordinated iron(II) centers in 1, 2, 3·2CHCl3, 4, 5, and 5·2CH3OH have two bidentate triazole ligands equatorially bound and two axial NCE co-ligands trans-coordinated. All structures are high spin (HS) at 100 K, except 3·2CHCl3, which is low spin (LS). Solid-state magnetic measurements show that only 3·2CHCl3 (T1/2 above 400 K) and 5·1.5H2O (T1/2 = 110 K) undergo spin crossover (SCO); the others remain HS at 300-50 K. When 3·2CHCl3 is heated at 400 K it desorbs CHCl3 becoming 3, which remains HS at 400-50 K. UV-Vis studies in CH2Cl2, CHCl3, (CH3)2CO, CH3CN, and CH3NO2 solutions for the BH3 analogues 3 and 6 led to a 6:1 ratio of Lnpyrimidine/Fe(II) being employed for the solution studies. These revealed SCO activity in all five solvents, with T1/2 values for the 2-pyrimidine complex (247-396 K) that were consistently higher than for the 4-pyrimidine complex (216-367 K), regardless of solvent choice, consistent with the 2-pyrimidine ring providing a stronger ligand field than the 4-pyrimidine ring. Strong correlations of solvent polarity index with the T1/2 values in those solvents are observed for each complex, enabling predictable T1/2 tuning by up to 150 K. While this correlation is tantalizing, here it may also be reflecting solvent-dependent speciation - so future tests of this concept should employ more stable complexes. Differences between solid-state (ligand field; crystal packing; solvent content) and solution (ligand field; solvation; speciation) effects on SCO are highlighted.
- Rodríguez-Jiménez, Santiago,Barltrop, Alexis S.,White, Nicholas G.,Feltham, Humphrey L. C.,Brooker, Sally
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p. 6266 - 6282
(2018/06/14)
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- Sulfur promoted decarboxylative thioamidation of carboxylic acids using formamides as amine proxy
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An efficient decarboxylative thioamidation of arylacetic and cinnamic acids has been developed employing formamides as amine surrogate and sulfur as promoter. Thioamides with variant structural features are obtained under mild reaction conditions without the use of transition metal catalysts and oxidants.
- Kumar, Saurabh,Vanjari, Rajeshwer,Guntreddi, Tirumaleswararao,Singh, Krishna Nand
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p. 2012 - 2017
(2016/04/05)
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- Decomposition of benzoylthioureas into benzamides and thiobenzamides under solvent-free conditions using iodine-alumina as the catalyst and its mechanistic study by density functional theory
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The breaking down of benzoylthioureas to benzamides and thiobenzamides in a single route using iodine-alumina as the catalyst under solvent-free conditions is highlighted. Results show that when an electron donating group, such as the methyl or methoxy group, is at the para-position of the aryl group of 1, benzamide (2) is the favoured product. When an electron withdrawing group, such as the chlorine or nitro group, is at the para-position of the aryl group of 1, thiobenzamide (3) is the favoured product. From the study of the reaction mechanism, it may be postulated that the formation of benzamide is due to the migration of the aryl group, whereas the formation of thiobenzamide may be due to the migration of the phenyl group. Thus, a new method for the formation of benzamides and thiobenzamides was developed.
- Nahakpam, Lokendrajit,Chipem, Francis A. S.,Chingakham, Brajakishor S.,Laitonjam, Warjeet S.
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supporting information
p. 2240 - 2247
(2015/03/18)
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- Organocatalytic, difluorocarbene-based S-difluoromethylation of thiocarbonyl compounds
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Upon treatment with trimethylsilyl 2,2-difluoro-2-fluorosulfonylacetate (TFDA) and a catalytic amount of N,N,N′,N′-tetramethyl-1,8-diaminonaphthalene, secondary thioamides and thiocarbamates undergo selective difluoromethylation on the sulfur atom to give S-difluoromethyl thioimidates and thioiminocarbonates in good yields, respectively. This is the first report on the synthesis of acyclic difluoromethyl thioimidates and thioiminocarbonates. The key for S-difluoromethylation is the organocatalytic generation of difluorocarbene (:CF2) under mild conditions, which prevents decomposition of the substrates. This process provides an efficient approach to pharmaceuticals and agrochemicals bearing a difluoromethylsulfanyl group, starting from widely available thiocarbonyl compounds.
- Fuchibe, Kohei,Bando, Masaki,Takayama, Ryo,Ichikawa, Junji
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p. 133 - 138
(2015/03/04)
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- Organocatalytic syntheses of benzoxazoles and benzothiazoles using aryl iodide and oxone via C-H functionalization and C-O/S bond formation
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An organocatalytic protocol for the syntheses of 2-substituted benzoxazoles and benzothiazoles is described from alkyl-/arylanilides and alkyl-/arylthioanilides using 1-iodo-4-nitrobenzene as catalyst and oxone as an inexpensive and environmentally safe terminal oxidant at room temperature in air via oxidative C-H functionalization and C-O/S bond formation. The procedure is simple and general and provides an effective route for the construction of functionalized 2-alkyl-/arylbenzoxazoles and 2-alkyl-/arylbenzothiazoles with moderate to high yields. The synthetic and mechanistic aspects have been described.
- Alla, Santhosh Kumar,Sadhu, Pradeep,Punniyamurthy, Tharmalingam
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p. 7502 - 7511
(2014/09/16)
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- Decarboxylative thioamidation of arylacetic and cinnamic acids: A new approach to thioamides
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A new decarboxylative strategy has been developed for the synthesis of thioamides via a three-component reaction involving arylacetic or cinnamic acids, amines and elemental sulfur powder, without the need of a transition metal and an external oxidant.
- Guntreddi, Tirumaleswararao,Vanjari, Rajeshwer,Singh, Krishna Nand
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supporting information
p. 3624 - 3627
(2014/08/05)
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- Sulfonic acid functionalized nano Γ-Al 2O 3: A new, efficient, and reusable catalyst for synthesis of thioamides
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Sulfonic acid functionalized nano γ-Al2O3 is easily prepared by the reaction of nano γ-Al2O3 with 1,3-propane sulfone. This reagent can be used as an eficient catalyst for the synthesis of thioamides. This new method consistently has the advantages of excellent yields and short reaction times. Further, the catalyst can be recovered for several times.
- Yin, Zhikui,Zheng, Bin,Ai, Fang
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p. 1412 - 1420
(2013/10/08)
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- Nano n -propylsulfonated magnetic γ-Fe2O3 as an efficient and reusable catalyst for the synthesis of thioamides
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One-pot three-component reactions of aldehydes, amines, and sulfur are carried out in the presence of nano n-propylsulfonated magnetic γ-Fe2O3 as a catalyst for the synthesis of biologically interesting thioamide derivatives. The value of this catalytic method lies in its mild reaction catalyst and conditions, good yields, and ease of handling.
- Yin, Zhikui,Zheng, Bin
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p. 527 - 531
(2013/10/21)
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- Synthesis of thioamides by catalyst-free three-component reactions in water
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Three-component reactions involving amines, aldehydes, and elemental sulfur powder are reported to afford thioamides in a simple one-pot procedure in the absence of a catalyst. A variety of thioamides can be obtained in good to excellent yields up to 88 %. Three-component reactions involving amines, aldehydes, and sulfur powder afford thioamides in a simple one-pot procedure. A variety of substituted thioamides are obtained in good to excellent yields up to 88 %. Copyright
- Xu, Hualong,Deng, Hang,Li, Zhengkai,Xiang, Haifeng,Zhou, Xiangge
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supporting information
p. 7054 - 7057
(2013/11/06)
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- Sulfated tungstate: An efficient catalyst for synthesis of thioamides via Kindler reaction
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New application of sulfated tungstate, a mildly acidic solid inorganic acid, as reusable heterogeneous catalyst for efficient Kindler reaction, a three component reactions of aldehydes, amines and sulfur, for synthesis of thioamides is discussed.
- Pathare, Sagar P.,Chaudhari, Pramod S.,Akamanchi, Krishnacharya G.
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experimental part
p. 125 - 129
(2012/07/03)
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- Homoleptic tris-cyclometalated iridium complexes with 2-phenylbenzothiazole ligands for highly efficient orange OLEDs
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Homoleptic tris-cyclometalated iridium(iii) complexes containing 2-phenylbenzothiazole derivatives as ligands have been successfully synthesized and characterized for the first time. Electron-donating (CH3, OCH3) and -withdrawing groups (F) were introduced into the 6-position of the benzothiazole moiety in the ligands to verify their influence on the optical and electronic properties of the complexes. Organic light-emitting diodes using these iridium complexes as doped emitters exhibited orange electrophosphorescence with excellent performances. An extremely high brightness of 95800 cd m-2 and a maximum luminance efficiency of 87.9 cd A -1 (46.0 lm W-1) were achieved for the pristine complex without any substituent in the ligand. These performances represent a significant improvement for vacuum-deposited orange OLEDs and the new record of the efficiencies for orange OLEDs reported so far. The substituents in the ligand were observed to be rather unimportant to influence the performance of this series of iridium complexes.
- Wang, Renjie,Liu, Di,Ren, Huicai,Zhang, Ting,Wang, Xinzeng,Li, Jiuyan
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p. 15494 - 15500
(2012/01/17)
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- Conversion of thiobenzamides to benzothiazoles via intramolecular cyclization of the aryl radical cation
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A new and general method has been developed for the intramolecular cyclization of thiobenzamides to benzothiazoles via aryl radical cations as reactive intermediates. The method utilizes phenyliodine(III) bis(trifluoroacetate) (PIFA) in trifluoroethanol or cerium ammonium nitrate (CAN) in aqueous acetonitrile at room temperature to effect cyclization within 30 min in moderate yields.
- Downer-Riley, Nadale K.,Jackson, Yvette A.
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p. 7741 - 7744
(2008/12/20)
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- Facile preparation of amides from thioamides by ceric ammonium nitrate
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Ceric ammonium nitrate (CAN) is found to be a good oxidizing agent which converts thioamides into their oxygen analogues in aqueous acetic acid under very mild conditions.
- Movassagh, Barahman,Meibodi, Forhatosadat,Sobhani, Shahin
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p. 1296 - 1298
(2007/10/03)
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- Kinetics and mechanism of the aminolysis of phenyl dithiobenzoates
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The kinetics and mechanism of the reactions of phenyl dithiobenzoates with anilines in acetonitrile at 55.0 deg C have been studied.The large magnitude of βx(βnuc) and the signs of cross-interaction constants, ρeXY > 0, ρYZ XZ > 0, are all consistent with the carbonyl addition mechanism in which the breakdown of the tetrahedral intermediate, T+/-, is rate limiting.The thiocarbonyl group (C=S) is found to favour amine expulsion in contrast to the carbonyl group (C=O) which favours the S-bonded nucleofuge expulsion from T+/-.The signs of cross-interaction constants, ρXY, ρYZ and/or ρXZ, are shown to provide useful mechanistic criteria for distinguishing, especially, the carbonyl addition mechanism involving the rate-limiting breakdown of the tetrahedral intermediate (T+/- from the concerted SN2 mechanism.
- Oh, Hyuck Keun,Shin, Chul Ho,Lee, Ikchoon
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p. 1169 - 1174
(2007/10/02)
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- Preparation and reactions of 5-Aryl-1,4,2-dithiazolium salts
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S-Thioaroylsulfenamides (ArCSSNH2), formed by reaction of ArCSS-Na+ with hydroxylamine-O-sulfonic acid, were aroylated or acylated to give N-aroyl- or N-acyl-S-thioaroylsulfenamides, respectively, which were then cyclized with dehydration to afford 3-substituted 5-aryl-1,4,2-dithiazolium salts. The behavior of 3,5-diphenyl-1,4,2-dithiazolium Perchlorate toward nucleophiles such as active methylene and amino compounds was studied systematically. The reaction can be classified into two cases depending on fission modes of initial adducts, i.e., ring opening-ring closure reaction (Path B) and fragmentation of dithiazole ring (Path C), and in some cases the initial adducts were isolated.
- Yonemoto, Katsumi,Shibuya, Isao,Tsuchiya, Tohru,Masahiko Yasumoto,Taguchi, Yoichi
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p. 2933 - 2937
(2007/10/02)
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- ANTIMYCOBACTERIAL THIOBENZANILIDES
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A group of 30 thiobenzanilides active against Mycobacterium kansasii have been synthesized and their 1H NMR and UV spectra and RM values (TLC on silica gel impregnated with methylsilicone oil) have been measured.From the correlation between the chemical shifts of the thioamide proton in the 1H NMR spectra and the Hammett constants it can be concluded that the substituents in both aromatic rings uniformly affect the electron density of the thioamide group.The antimycobacterial activity is probably connected with local molecular parameters and can be considered to be approximately additive with respect to both parts of the molecule.
- Waisser, Karel,Houngbedji, Nestor,Machacek, Milos,Sekera, Miroslav,Urban, Josef,Odlerova, Zelmira
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p. 307 - 316
(2007/10/02)
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- Reaction of N,N-Dimethyl-N'-thiobenzoylformamidine and N,N-Dimethyl-N'-phenylthiocarbamoylformamidine with N-Arylbenzimidoyl Chlorides
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The reactions of N,N-dimethyl-N'-thiobenzoylformamidine (1) and N,N-dimethyl-N'-phenylthiocarbamoylformamidine (4) with N-arylbenzimidoyl chlorides (2) have been studied.Compound 1 reacts with 2 in dry chloroform at room temperature to give dimidoyl sulphides (3) in good yields.However, the reaction of 2 with 4 in dry tetrahydrofuran under reflux results in the formation of a mixture of thiobenzanilides (5) and N-aryl-N'-phenylbenzamidines (6).Possible mechanistic pathways for these reactions have been suggested.
- Baruah, P. D.,Roy, G.,Satsangi, R.,Mahajan, M. P.
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p. 357 - 359
(2007/10/02)
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