- Metal-free C-Se cross-coupling enabled by photoinduced inter-molecular charge transfer
-
Metal-free C-Se cross-couplingsviathe formation of electron-donor-acceptor (EDA) complexes have been developed. The visible-light induced reactions can be applied for the synthesis of a series of unsymmetrical diaryl selenides employing aryl bromides, aryl iodides as well as aryl chlorides under mild reaction conditions. The scale-up was readily achieved. UV-Vis spectroscopy measurements provide insight into the reaction mechanism.
- Rueping, Magnus,Yue, Huifeng,Zhu, Chen,Zhumagazy, Serik
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supporting information
p. 96 - 99
(2021/12/29)
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- Palladium-Catalyzed Carbonylative Synthesis of Aryl Selenoesters Using Formic Acid as an Ex Situ CO Source
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A new catalytic protocol for the synthesis of selenoesters from aryl iodides and diaryl diselenides has been developed, where formic acid was employed as an efficient, low-cost, and safe substitute for toxic and gaseous CO. This protocol presents a high functional group tolerance, providing access to a large family of selenoesters in high yields (up to 97%) while operating under mild reaction conditions, and avoids the use of selenol which is difficult to manipulate, easily oxidizes, and has a bad odor. Additionally, this method can be efficiently extended to the synthesis of thioesters with moderate-to-excellent yields, by employing for the first time diorganyl disulfides as precursors.
- Yano De Albuquerque, Danilo,Teixeira, Wystan K. O.,Sacramento, Manoela Do,Alves, Diego,Santi, Claudio,Schwab, Ricardo S.
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supporting information
p. 595 - 605
(2022/01/12)
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- Trichloroisocyanuric Acid-Promoted Synthesis of Arylselenides and Aryltellurides from Diorganyl Dichalcogenides and Arylboronic Acids at Ambient Temperature
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A transition-metal-free method for the synthesis of arylselenides and aryltellurides has been established based on the oxidative cross-coupling between diorganyl dichalcogenides and aryl boronic acids. With trichloroisocyanuric acid as an oxidant, the reaction proceeded smoothly to afford the desired products in 45–97% yields at ambient temperature. Three reaction reagents used in this method are stoichiometric and the oxidation by-product isocyanuric acid can be easily isolated and recovered. Besides of arylboronic acids, aryl trifluoroborates and aryl trihydroxyborates salts are also able to perform this transformation. (Figure presented.).
- Sun, Nan,Zheng, Kai,Sun, Pengyuan,Chen, Yang,Jin, Liqun,Hu, Baoxiang,Shen, Zhenlu,Hu, Xinquan
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p. 3577 - 3584
(2021/06/15)
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- Forging C?S(Se) Bonds by Nickel-catalyzed Decarbonylation of Carboxylic Acid and Cleavage of Aryl Dichalcogenides
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A nickel-catalyzed decarbonylation of carboxylic acids cross-coupling protocol has been developed for the straightforward C?S(Se) bond formation. This reaction is promoted by a commercially-available, user-friendly, inexpensive, air and moisture-stable nickel precatalyst. Various carboxylic acids and a wide range of aryl dichalcogenide substrates were tolerated in this process which afforded products in good to excellent yields. In addition, the present reaction can be conducted on gram scale in good yield.
- Zhou, Jing-Ya,Zhu, Yong-Ming
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p. 2452 - 2461
(2021/06/28)
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- Electrochemical Thiolation and Borylation of Arylazo Sulfones with Thiols and B2pin2
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An efficient electrochemical synthesis approach of various unsymmetrical thioethers and arylboronates has been developed. Bench stable arylazo sulfones were used as radical precursors for carbon-heteroatom bond formation under electrochemical conditions. Moreover, the scalability of this approach was evaluated by performing the electrochemical thiolation and borylation of arylazo sulfones with thiols and B2pin2 on a gram scale. This protocol not only avoided the use of stoichiometric oxidants, metal catalysts, activating agents and even added bases, but also exhibited favorable functional group tolerance. (Figure presented.).
- Wang, Rongkang,Chen, Fangming,Jiang, Lvqi,Yi, Wenbin
-
supporting information
p. 1904 - 1911
(2021/02/12)
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- Metal-Free Synthesis of Unsymmetrical Aryl Selenides and Tellurides via Visible Light-Driven Activation of Arylazo Sulfones
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A protocol for the visible light driven preparation of unsymmetrical (hetero)aryl selenides and tellurides is described herein. The method exploits the peculiar photoreactivity of arylazo sulfones that act as thermally stable, precursors of aryl radicals under both photocatalyst- and additive-free conditions. The method developed shows an impressive versatility (more than fifty compounds isolated).
- Fagnoni, Maurizio,Li, Ankun,Li, Yuxuan,Liu, Junjie,Lu, Kui,Protti, Stefano,Shan, Xiwen,Tian, Miaomiao,Zhao, Xia
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supporting information
p. 7358 - 7367
(2020/12/01)
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- Method for preparing asymmetric organic selenium ether compounds through metal-free chemical oxidation method (by machine translation)
-
The method is mild in reaction condition, convenient to operate, high in 1 reaction condition, convenient 2 to operate, high in safety, wide in substrate range, high 2 - 8h in yield, particularly suitable for reaction of various poor 3 electric and sterically hindered arylboronic acid and diselenoxy ether, and capable of finishing most of the reaction 4h. (by machine translation)
- -
-
Paragraph 0059-0062; 0064
(2020/12/09)
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- Nickel(II) Tetraphenylporphyrin as an Efficient Photocatalyst Featuring Visible Light Promoted Dual Redox Activities
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Nickel(II) tetraphenylporphyrin (NiTPP) is presented as a robust, cost-effective and efficient visible light induced photoredox catalyst. The ground state electrochemical data (CV) and electronic absorption (UV-Vis) spectra reveal the excited state redox potentials for [NiTPP]*/[NiTPP].? and NiTPP].+/[NiTPP]* couples as +1.17 V and ?1.57 V vs SCE respectively. The potential values represent NiTPP as a more potent photocatalyst compare to the well-explored [Ru(bpy)3]2+. The non-precious photocatalyst exhibits excited state redox reactions in dual fashions, i. e., it is capable of undergoing both oxidative as well as reductive quenching pathways. Such versatility of a photocatalyst based on first-row transition metals is very scarce. This unique phenomenon allows one to perform diverse types of redox reactions by employing a single catalyst. Two different sets of chemical reactions have been performed to represent the synthetic utility. The catalyst showed superior efficiency in both carbon-carbon and carbon-heteroatom bond-forming reactions. Thus, we believe that NiTPP is a valuable addition to the photocatalyst library and this study will lead to more practical synthetic applications of earth-abundant-metal-based photoredox catalysts. (Figure presented.).
- Mandal, Tanumoy,Das, Sanju,De Sarkar, Suman
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supporting information
p. 3200 - 3209
(2019/05/16)
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- Iron(0) nanoparticles mediated direct conversion of aryl/heteroaryl amines to chalcogenides via in situ diazotization
-
A simple procedure for the synthesis of organo-chalcogenides has been developed by the reaction of aryl/heteroaryl amines with di-aryl/heteroaryl dichalcogenides in the presence of tBuONO and Fe(0) nanoparticles. The reaction proceeds via in situ diazotization followed by chalcogenation. A series of functionalized diaryl/aryl heteroaryl/diheteroaryl/aryl-alkyl selenides, sulfides and tellurides have been obtained by this procedure. Significantly, using this procedure 2,4-dinitroaniline is converted to (2,4-dinitrophenyl)(phenyl)selane which is known as thioredoxin reductase (TR) and glutathione reductase (GR) inhibitor. The reaction goes by a radical pathway and a plausible mechanism has been suggested.
- Panja, Subir,Maity, Pintu,Kundu, Debasish,Ranu, Brindaban C.
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supporting information
p. 3441 - 3445
(2017/08/10)
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- A Highly Efficient Copper-Catalyzed Synthesis of Unsymmetrical Diaryl- and Aryl Alkyl Chalcogenides from Aryl Iodides and Diorganyl Disulfides and Diselenides
-
An efficient and convenient protocol has been developed for the copper-catalyzed reaction of aryl iodides and diorganyl disulfides and diselenides. A variety of symmetrical and unsymmetrical diaryl- and aryl alkyl chalcogenides were synthesized with good functional group tolerance and chemoselectivity by using copper(I) iodide as a catalyst, 4′-(4-methoxyphenyl)-2,2′:6′,2′′-terpyridine as ligand, and KOH as base under an inert atmosphere.
- Movassagh, Barahman,Hosseinzadeh, Zhila
-
supporting information
p. 777 - 781
(2016/03/12)
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- METHOD OF PREPARING CORE-SHELL COPPER NANOPARTICLES IMMOBILIZED ON ACTIVATED CARBON AND METHOD OF PREPARING CHALCOGENIDE COMPOUND USING NANOPARTICLES AS CATALYST
-
Disclosed herein is a method of preparing a Cu/Cu2O core-shell copper nanoparticle catalyst having high catalytic activity from [Cu3(BTC)2] and NaBH4 via a simple chemical reduction method. Also disclosed is a method of preparing a chalcogenide compound by using the nanoparticle catalyst as a heterogeneous catalyst in a cross-coupling reaction between a chalcogenide precursor compound and a boron-containing compound. The disclosed cross-coupling reaction is performed via a simple process, and the disclosed nanoparticle catalyst is compatible with various substrates under mild reaction conditions and exhibits excellent recyclability without a reduction in catalytic activity.
- -
-
Paragraph 0056; 0065
(2016/11/14)
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- Synthesis of unsymmetrical diorganyl chalcogenides under greener conditions: Use of an iodine/DMSO system, solvent- and metal-free approach
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Herein, we report a greener iodine-catalyzed protocol to access different types of unsymmetrical diorganyl chalcogenides. This new approach works in the absence of solvent and metal. The desired products were obtained in good to excellent yields using one equivalent of arylboronic acids, half an equivalent of various diorganyl dichalcogenides, iodine (10 mol%) as a catalyst and 2 equivalents of dimethyl sulfoxide (DMSO; as oxidant), with a reaction time of 10 min under microwave irradiation.
- Saba, Sumbal,Rafique, Jamal,Braga, Antonio L.
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supporting information
p. 1446 - 1452
(2015/05/27)
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- Copper nanoparticles catalyzed Se(Te)-Se(Te) bond activation: A straightforward route towards unsymmetrical organochalcogenides from boronic acids
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A highly porous copper metal-organic framework, [Cu3(BTC)2] (BTC=benzene-1,3,5-tricarboxylate) was synthesized and used as a precursor for the synthesis of copper nanoparticles (NPs) and characterized by several techniques, including XRD, SEM, TEM, EDX and BET measurements. The as-synthesized copper nanoparticles were immobilized onto activated charcoal (AC) by means of ultrasonication at room temperature without any pretreatment. The Cu NPs/AC was employed as a heterogeneous catalyst for the cross-coupling of diphenyl diselenide and boronic acids to form diphenyl selenides through Se-Se bond activation under ligand-, base-, and additive-free conditions. The copper NPs/AC, which combines the architecture of MOFs and the high surface area of charcoal, could be an efficient heterogeneous catalytic system that is compatible with a variety of substituents on diphenyl selenides. Its promising catalytic activity relative to that of other homogeneous systems and low catalyst loading for the synthesis of unsymmetrical diaryl selenides is an important application in the area of nanocatalysis. The Cu NPs/AC catalyst, which exhibits excellent catalytic activity and remarkable tolerance to a wide variety of substituents, led to Se sp3-, sp2-, and sp-carbon bond formation by using DMSO as a solvent and atmospheric air as oxidant. This approach can also be extended to the preparation of unsymmetrical organotelluride derivatives. Three-in-one catalyst: Copper nanoparticles on activated charcoal show excellent catalytic activity towards the synthesis of unsymmetrical chalcogenides, starting from boronic acids, in air under ligand-, base-, and additive-free conditions, and resulting in selenium sp3-, sp2-, and sp-carbon bond formation.
- Mohan, Balaji,Yoon, Chohye,Jang, Seongwan,Park, Kang Hyun
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p. 405 - 412
(2015/03/04)
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- A convenient and efficient copper-catalyzed synthesis of unsymmetrical and symmetrical diaryl chalcogenides from arylboronic acids in ethanol at room temperature
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A simple and convenient approach for the synthesis of unsymmetrical diaryl chalcogenides (Te, Se, and S) has been developed by copper-catalyzed cross-coupling reaction of organoboronic acid with diaryl dichalcogenide in ethanol using NaBH4 in air or oxygen. The present methodology is highly practical for the synthesis of unsymmetrical diaryl tellurides with various functionalities such as -NO2, -F, -Br, and -COOH that have been obtained in good to excellent yields. Methodology is also effective for the synthesis of unsymmetrical diaryl selenides and sulfides. Moreover, symmetrical diaryl selenides have also been obtained from arylboronic acids using elemental selenium powder under optimized reaction conditions. The use of NaBH 4 is the key for the development of milder reaction conditions, which enable the construction of unsymmetrical diaryl chalcogenides from boronic acid substrates in ethanol at room temperature.
- Kumar, Amit,Kumar, Sangit
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p. 1763 - 1772
(2014/03/21)
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- Visible light photocatalyzed direct conversion of aryl-/heteroarylamines to selenides at room temperature
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A novel strategy for the direct conversion of aryl- and heteroarylamines to selenides has been developed via diazotization of amines with tert-butyl nitrite in neutral medium followed by reaction with diaryl/diheteroaryl/dialkyl diselenides in one pot under photocatalysis at room temperature in the absence of any metal. This reaction is also applied for the synthesis of tellurides. The selenylation of heteroarylamine by this protocol is of much significance because of the difficulty in diazotization of these molecules by a standard diazotization method in acid medium.
- Kundu, Debasish,Ahammed, Sabir,Ranu, Brindaban C.
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supporting information
p. 1814 - 1817
(2014/04/17)
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- Copper-catalyzed C-Se coupling of diphenyl diselenide with arylboronic acids at room temperature
-
An efficient synthetic protocol for the Cu-catalyzed cross-coupling of diphenyl diselenide and arylboronic acid at room temperature was described. This catalytic system could tolerate a variety of arylboronic acids with only 3 mol % amount of CuSO4 as the catalyst and inexpensive 1,10-phen. H 2O as the ligand. Moreover, this catalytic system used environment-friendly EtOH as the solvent and catalytic amount of Na 2CO3 (20 mol %) as the base in the air.
- Zheng, Bo,Gong, Ying,Xu, Hua-Jian
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p. 5342 - 5347
(2013/06/27)
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- A general and green procedure for the synthesis of organochalcogenides by CuFe2O4 nanoparticle catalysed coupling of organoboronic acids and dichalcogenides in PEG-400
-
A general and efficient procedure has been developed for the synthesis of organochalcogenides (selenides and tellurides) by a simple reaction of organoboronic acids and dichalcogenides catalysed by CuFe2O 4 nanoparticles in PEG-400 without any ligand. This protocol offers the scope for access to a wide spectrum of chalcogenides including diaryl, aryl-heteroaryl, aryl-styrenyl, aryl-alkenyl, aryl-allyl, aryl-alkyl and aryl-alkynyl versions. The catalyst is magnetically separable and recyclable eight times without any loss of appreciable catalytic activity. The products are obtained in high purities after evaporation of solvent followed by filtration column chromatography. The Royal Society of Chemistry.
- Kundu, Debasish,Mukherjee, Nirmalya,Ranu, Brindaban C.
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p. 117 - 125
(2013/04/10)
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- Reaction under ball-milling: Solvent-, ligand-, and metal-free synthesis of unsymmetrical diaryl chalcogenides
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A convenient, efficient, and general procedure for the synthesis of diaryl chalcogenides including sulfides, selenides and tellurides has been developed by the reaction of diazonium tetrafluoroborates and diaryl dichalcogenides on the surface of alumina u
- Mukherjee, Nirmalya,Chatterjee, Tanmay,Ranu, Brindaban C.
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p. 11110 - 11114
(2013/11/19)
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- Microwave-assisted reaction of aryl diazonium fluoroborate and diaryl dichalcogenides in dimethyl carbonate: A general procedure for the synthesis of unsymmetrical diaryl chalcogenides
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A convenient, general and efficient procedure for the synthesis of unsymmetrical diaryl chalcogenides has been developed by the reaction of aryl diazonium fluoroborates and diaryl dichalcogenides in the presence of zinc dust in dimethyl carbonate under microwave irradiation. The reactions of a wide range of substituted aryl diazonium fluoroborates and diaryl dichalcogenides have been addressed. The zinc dust is required for the cleavage of diaryl dichalcogenides. The products are obtained in high purity after fast column chromatography of the crude residue after evaporation of dimethyl carbonate. The Royal Society of Chemistry 2012.
- Kundu, Debasish,Ahammed, Sabir,Ranu, Brindaban C.
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experimental part
p. 2024 - 2030
(2012/07/17)
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- An efficient copper(I) iodide catalyzed synthesis of diaryl selenides through Cse bond formation using solvent acetonitrile as ligand
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A wide range of diaryl selenides can be synthesized through CSe bond formation using readily available copper(I) iodide as catalyst under mild reaction conditions (82C) from aryl iodides and diphenyl diselenide. In this coupling reaction, solvent acetonitrile acts as ligand for copper(I) iodide and no external ligand is required. Less reactive aryl bromides also provide the di-aryl selenides in good isolated yields. Georg Thieme Verlag Stuttgart ? New York.
- Dandapat, Arpan,Korupalli, Chiranjeevi,Prasad,Singh, Rahul,Sekar, Govindasamy
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experimental part
p. 2297 - 2302
(2011/09/16)
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- CuS/Fe: A novel and highly efficient catalyst system for coupling reaction of aryl halides with diaryl diselenides
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The CuS catalyzed coupling reactions of aryl halides and diaryl diselenides were accelerated by the addition of Fe powder in only 3-12 h with good to excellent yields. SEM-EDX indicated that the in situ iron oxides as support against catalyst agglomeration accelerated the reaction. This catalyst system was also demonstrated recyclable without significant loss of catalytic activity.
- Li, Yaming,Wang, Huifeng,Li, Xiaoying,Chen, Tao,Zhao, Defeng
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supporting information; experimental part
p. 8583 - 8586
(2010/11/17)
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- Al2O3-Supported Cu-catalyzed electrophilic substitution by PhSeBr in organoboranes, organosilanes, and organostannanes. A protocol for the synthesis of unsymmetrical diaryl and alkyl aryl selenides
-
(Figure Presented) Alumina-supported copper sulfate efficiently catalyzes electrophilic substitution in organoborane, organosilanes, and organostannanes by phenylselenium bromide providing a novel and efficient route to the synthesis of unsymmetrical diaryl and alkyl aryl selenides. A series of aryl, alkyl, and heteroaryl phenyl selenides were obtained in high yields. The catalyst is inexpensive, eco- and user-friendly, and recyclable. The mechanism involving Cu-assisted nucleophilic displacement of Br in PhSeBr by mild nucleophiles is described.
- Bhadra, Sukalyan,Saha, Amit,Ranu, Brindaban C.
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experimental part
p. 4864 - 4867
(2010/10/18)
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- Copper nano-catalyst: Sustainable phenyl-selenylation of aryl iodides and vinyl bromides in water under ligand free conditions
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A simple and efficient procedure for the synthesis of aryl- and vinyl-selenides has been developed by a copper nanoparticle catalysed reaction of aryl iodide/vinyl bromide with diphenyl diselenide in the presence of zinc in water. (E)-Vinyl bromides produce (E)-vinyl selenides stereoselectively, whereas (Z)-vinyl bromides provide mixtures of (E) and (Z) isomers. The catalyst was recycled.
- Saha, Amit,Saha, Debasree,Ranu, Brindaban C.
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experimental part
p. 1652 - 1657
(2009/06/28)
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- Enantiomerically pure organoseleno-1-arylethanols by enzymatic resolution with Candida antarctica lipase: Novozym 435
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Racemic organoseleno-1-arylethanols were prepared by ortho-lithiation of arylethanols, followed by sequential reaction with elemental selenium and alkyl halides and by reaction of either aryldiazonium chlorides with diphenyldiselenide or with lithium and
- Omori, Alvaro T.,Assis, Leonardo F.,Andrade, Leandro H.,Comasseto, Joao V.,Porto, Andre L.M.
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p. 1048 - 1053
(2008/02/08)
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- Palladium-catalyzed phenyl-selenylation with n-Bu3SnSePh in one-pot two-step reactions
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We have studied the Pd-catalyzed cross-coupling reaction of a stannane derived from selenium n-Bu3SnSePh (1) with aryl and perfluoroalkyl iodides. Herein a very efficient one-pot two-step selenylation reaction to form a C-Se bond is reported. Ph2Se2 reacts with Na metal in liquid ammonia yielding PhSe- ions. To this solution n-Bu3SnCl was added to afford 1, which was introduced in the palladium-catalyzed coupling reaction without isolation. These reactions afford functionalized diarylselenides and phenylperfluroalkyl selenides from good to high yields (38-98%).
- Bonaterra, Mariana,Martín, Sandra E.,Rossi, Roberto A.
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p. 3511 - 3515
(2007/10/03)
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- Methods for formation of aryl-sulfur and aryl-selenium compounds using copper(I) catalysts
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A mild, palladium-free synthetic protocol for the cross-coupling reaction of vinyl or aryl iodides and thiols or selenols using, in certain embodiments, 10 mol % CuI and 10 mol % neocuproine, with NaOt-Bu as the base, in toluene at 110 ° C. A variety of vinyl/aryl sulfides and vinyl/aryl selenides can be synthesized in excellent yields from readily available iodides and thiols or selenols.
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Page/Page column 17-18; 44
(2008/06/13)
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- A simple copper salt-catalyzed synthesis of unsymmetrical diaryl selenides and tellurides from arylboronic acids with diphenyl diselenide and ditelluride
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In the presence of a catalytic amount of simple copper salt, the reaction of arylboronic acids with diphenyl diselenide and ditelluride was accomplished without any additive to afford the corresponding unsymmetrical diarylselenides and tellurides in good yields. Georg Thieme Verlag Stuttgart.
- Wang, Lei,Wang, Min,Huang, Fuping
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p. 2007 - 2010
(2007/10/03)
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- Preparation of chiral organochalcogeno-α-methylbenzyl alcohols via biocatalysis. The role of Daucus carota root
-
A series of organochalcogeno acetophenones 3 has been submitted to the action of enzymes from Daucus carota root. Some of the chalcogeno ketones tested afforded the chiral organochalcogeno-α-methylbenzyl alcohols 4 in excellent enantiomeric excesses (>99%), under mild and environmentally friendly conditions. The stereoselectivity of the reduction is in accordance with Prelog's rule. Enzymatic kinetic resolution as alternative process was used to obtain the chiral ortho-organochalcogeno-α-methylbenzyl alcohols in excellent enantiomeric excess (>99%).
- Comasseto, Jo?o V.,Omori, álvaro T.,Porto, André L. M.,Andrade, Leandro H.
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p. 473 - 476
(2007/10/03)
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- A general method for the formation of diaryl selenides using copper(I) catalysts
-
We report a mild, palladium-free synthetic protocol for the cross coupling reaction of aryl iodides and phenyl selenol using 10 mol% CuI/neocuproine, NaOt-Bu or K2CO3 as base, in toluene, at 110°C. Using this protocol, we show that a variety of diaryl selenides can be synthesized in good yields from commercially available aryl iodides.
- Gujadhur, Rattan K.,Venkataraman
-
-
- Tributyltin aryl selenides as efficient arylselenating agents. Synthesis of diaryl and aryl organyl selenides
-
Tributyltin aryl selenides are highly efficient arylselenating agents in reactions with aryl iodides and aryl triflates under catalysis with Pd and Ni complexes respectively. They also may be used as efficient source of active arylselenolate anion in the
- Beletskaya,Sigeev,Peregudov,Petrovskii
-
p. 1463 - 1475
(2007/10/03)
-
- New approaches to the synthesis of unsymmetrical diaryl selenides
-
Unsymmetrical diaryl selenides PhSeAr were obtained by the palladium catalysed reactions of aryl (heteroaryl) iodide or triflate with Bu3SnSePh in high yields. The same compounds can be obtained by the non-catalytic reactions of Bu3SnSePh with ArN2BF4 or (ArN2)2ZnCl4.
- Beletskaya, Irina P.,Sigeev, Alexander S.,Peregudov, Alexander S.,Petrovskii, Pavel V.
-
-
- Preparation and Diels-Alder Reactivity of Several New Chalcogen-Halogen Substituted Butadienes
-
Addition of halogens and pseudohalogens across one ?-bond of 1,4-dichlorobut-2-yne, followed by a 1,4-elimination, is an efficient synthesis of several new polysubstituted butadienes.If the product dienes have a sulfur or selenium substituent they are quite reactive, undergoing cycloaddition with the moderately reactive dienophile methyl vinyl ketone at 20 deg C in the presence of boron trifluoride etherate.The regiochemistry of the cycloadditions was elucidated, and the limitations of the methodology are discussed.
- Bridges, Alexander J.,Fischer, John W.
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p. 2954 - 2961
(2007/10/02)
-
- THE DIELS-ALDER REACTIVITY OF SOME NEW SULFUR (SELENIUM) SUBSTITUTED HALOBUTADIENES
-
3-PhS(e)-(1),2-(di)halobutadienes undergo BF3 catalysed cycloadditions with methyl vinyl ketone at 25 deg C, to give good yields of adducts in which the regiochemistry of addition is mainly controlled by the sulfur (selenium) atom.
- Bridges, Alexander J.,Fischer, John W.
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p. 447 - 450
(2007/10/02)
-