- (E)-alkenyl thiocyanates from (E)-alkenylpentafluorosilicates by the oxidative cleavage with copper(II) thiocyanate
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(E)-Alkenylpentafluorosilicates react with copper(II) thiocyanate in DMF at ambient temperature to give (E)-alkenyl thiocyanates stereoselectively in high yields.
- Tamao, Kohei,Kakui, Toshio,Kumada, Makoto
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Read Online
- Temperature-Controlled Chemoselective Synthesis of Thiosulfonates and Thiocyanates: Novel Reactivity of KXCN (X=S, Se) towards Organosulfonyl Chlorides
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An efficient chemoselective protocol has been developed for the synthesis of thiosulfonates and thiocyanates by employing cost effective and commercially available organosulfonyl chlorides with potassium thio-/selenocyanate. The strategy offered the thiosulfonates and thiocyanates selectively by tuning the equivalents of KSeCN and optimizing the reaction temperature. On the other hand, thiosulfonates were obtained as sole products when organosulfonyl chlorides were treated with KSCN. Furthermore, the syntheses of diarylthioethers and aryl(heteroaryl) thioethers were carried out as a part of synthetic application of newly prepared arylthiocyanates.
- Kalaramna, Pratibha,Goswami, Avijit
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supporting information
p. 5359 - 5366
(2021/10/25)
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- Synthesis of Thio-/Selenopyrrolines via SnCl4-Catalyzed (3+2)-Cycloadditions of Donor-Acceptor Cyclopropanes with Thio-/Selenocyanates
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A straightforward protocol has been developed to access thio-/selenopyrrolines through a (3+2)-cycloaddition of aryl thio-/selenocyanates with donor-acceptor cyclopropanes (DACs) in the presence of SnCl4 as a Lewis acid catalyst. Further, good chemoselectivity was observed when DACs were treated with 3-cyano phenyl thiocyanate. These results suggest that thiocyanate is more reactive than nitrile moiety in such (3+2)-cycloaddition reactions.
- Ali, Shamsad,Goswami, Avijit,Kalaramna, Pratibha,Singh, Prasoon Raj
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p. 4683 - 4689
(2021/09/10)
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- Selectfluor-initiated cyanation of disulfides to thiocyanates
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A Selectfluor-initiated cyanation of disulfides to thiocyanates has been developed. In this process, Selectfluor was employed as the oxidant and trimethylsilyl cyanide was used as the cyanation reagent. It provides an eco-friendly and simple way to synthesize the thiocyanates.
- Zhou, Pengpeng,Chen, Chuan,Li, Shubai
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p. 376 - 380
(2020/02/13)
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- An electrochemical method for deborylative seleno/thiocyanation of arylboronic acids under catalyst- And oxidant-free conditions
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An electrochemical deborylative seleno/thiocyanation of arylboronic acids has been well established to synthesize the corresponding aryl seleno/thiocyanates with good functional group tolerance under ambient conditions. A gram-scale reaction has been performed to highlight the advantages of the protocol. Preliminary mechanistic studies indicate that the oxidation of the seleno/thiocyanate anion occurs prior to that of the arylboronic acid substrate in galvanostatic mode, and that free radicals are involved in the process.
- He, Dongdong,Yao, Jiaojiao,Ma, Boling,Wei, Jinghao,Hao, Guangguo,Tuo, Xun,Guo, Shengmei,Fu, Zhengjiang,Cai, Hu
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supporting information
p. 1559 - 1564
(2020/03/26)
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- Fluorium-Initiated Dealkylative Cyanation of Thioethers to Thiocyanates
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Thioethers are converted to thiocyanates via fluorium-initiated dealkylative cyanation. Selectfluor is used as the oxidant, and trimethylsilyl cyanide is used as the cyanation reagent. The well-streamlined procedure is user-friendly, operationally simple, and step-economical. The current mechanistic studies show that the sulfur radical cation and cyano radical are both involved. They combine to deliver cyanosulfonium, an intermediate toward thiocyanate after dealkylation. Alternatively, a nucleophilic mechanism is also possible. Our dealkyaltive cyanation is also efficient in synthesizing thiocyanates with strongly electrophilic functionalities.
- Chen, Yang,Qi, Hongyi,Chen, Ning,Ren, Demin,Xu, Jiaxi,Yang, Zhanhui
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p. 9044 - 9050
(2019/08/12)
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- Electrochemical ipso-Thiocyanation of Arylboron Compounds
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An operationally simple electrochemical method for the transition-metal-free ipso-thiocyanation of arylboronic acids and aryl trifluoroborates has been developed. The SCN electrophile is generated in situ by anodic oxidation of thiocyanate anions, which avoids formation of salt waste and prevents unwanted side reactions arising from chemical oxidants. The reaction proceeds regiospecifically, and the scope extends to non-activated aromatic systems. (Figure presented.).
- Dyga, Marco,Hayrapetyan, Davit,Rit, Raja K.,Goo?en, Lukas J.
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supporting information
p. 3548 - 3553
(2019/04/26)
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- One-pot synthesis of (ethoxycarbonyl)difluoromethylthioethers from thiocyanate sodium and ethyl 2-(trimethylsilyl)-2,2-difluoroacetate (TMS-CF2CO2Et)
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An efficient one-pot cascade methodology for the synthesis of (ethoxycarbonyl)difluoromethyl thioethers is described. Benzyl, allyl, alkyl halides or diazonium salts as the starting materials together with thiocyanate sodium and TMS-CF2CO2Et in the presence of CsF or NaOAc afford a variety of the fluoroalkylthiolated products in moderate to good yields.
- Xu, Lijun,Wang, Hongyu,Zheng, Changwu,Zhao, Gang
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p. 6057 - 6066
(2017/09/23)
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- An efficient method for thiocyanation of aromatic and heteroaromatic compounds using cyanuric chloride and ammonium thiocyanate under conventional and nonconventional conditions
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Highly efficient thiocyanation of aromatic and heteroaromatic compounds has been accomplished by using cyanuric chloride (NCCl)3/NH4SCN in dichloromethane under conventional and ultrasonic-assisted conditions. Sonicated reactions rea
- Venkanna,Rajanna,Kumar, M. Satish,Venkateswarlu,Ali, M. Moazzam
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p. 237 - 240
(2016/01/20)
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- Transition-metal-free synthesis of thiocyanato- or nitro-arenes through diaryliodonium salts
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A transition-metal-free approach to facile synthesis of thiocyanato- and nitro-arenes was developed from KSCN (potassiumthiocyanate) or NaNO2with diaryliodonium salts in good yields under mild conditions. The reaction was compatible with a variety of sensitive functional substituents such as halides and nitro and ester groups. The usefulness of arylation products has been realized. (Formula Present).
- Li, Xiao-Hua,Li, Liang-Gui,Mo, Xue-Ling,Mo, Dong-Liang
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p. 963 - 970
(2016/07/07)
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- Molybdenum-doped α-MnO2 as an efficient reusable heterogeneous catalyst for aerobic sulfide oxygenation
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Oxygenation of sulfides to sulfoxides and/or sulfones is an important transformation, and the development of efficient heterogeneous catalysts for oxygenation, which can utilize O2 as the terminal oxidant, is highly desired. In this study, we have successfully developed manganese oxide-based efficient heterogeneous catalysts for aerobic oxygenation of sulfides. Firstly, we prepared four kinds of manganese oxides possessing different crystal structures, such as α-MnO2, β-MnO2, γ-MnO2, and δ-MnO2, and their structure-activity relationships were examined for the aerobic oxygenation of thioanisole. Amongst them, α-MnO2 showed the best catalytic performance for the oxygenation. Moreover, α-MnO2 was highly stable during the catalytic oxygenation possibly due to the tunnel K+ ions. In order to further improve the catalytic performance of α-MnO2, substitutional doping of transition metal cations, such as Mo6+, V5+, Cr3+, and Cu2+, into the framework was carried out. Undoped α-MnO2 possessed a fibrous morphology. When high-valent transition metal cations were doped, especially Mo6+, the lengths of the fibers drastically shortened to form grain-like aggregates of ultrafine nanocrystals, resulting in an increase in specific surface areas and the numbers of catalytically active surface sites. In the presence of Mo6+-doped α-MnO2 (Mo-MnO2), various kinds of sulfides could efficiently be oxidized to the corresponding sulfoxides as the major products. The observed catalysis was truly heterogeneous, and Mo-MnO2 could repeatedly be reused while keeping its high catalytic performance. Besides sulfide oxygenation, Mo-MnO2 could efficiently catalyze several aerobic oxidative functional group transformations through single-electron transfer oxidation processes, namely, oxygenation of alkylarenes, oxidative α-cyanation of trialkylamines, and oxidative S-cyanation of benzenethiols.
- Uematsu, Tsubasa,Miyamoto, Yumi,Ogasawara, Yoshiyuki,Suzuki, Kosuke,Yamaguchi, Kazuya,Mizuno, Noritaka
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p. 222 - 233
(2015/12/31)
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- Nitromethane as a cyanating reagent for the synthesis of thiocyanates
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Nitromethane has been developed to be an effective cyanating reagent for the synthesis of thiocyanates. In the presence of iodine and base, a wide range of disulfides were reacted with nitromethane smoothly to give diverse thiocyanates in moderate to good yields.
- Wang, Zuo-Hui,Ji, Xiao-Ming,Hu, Mao-Lin,Tang, Ri-Yuan
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supporting information
p. 5067 - 5070
(2015/08/06)
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- Transition-metal-free cross-coupling of thioethers with aryl(cyano)iodonium triflates: A facile and efficient method for the one-pot synthesis of thiocyanates
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A novel transition-metal-free cross-coupling method for the one-step synthesis of thiocyanates via the C-S bond cleavage of readily available thioethers with aryl(cyano)-iodonium triflates as the cyanating agent is developed. This process features relatively broad substrate scopes, less-toxic hypervalent iodine reagents, mild operating conditions, excellent functional group compatibilities, and affords various thiocyanates in moderate to good yields. This journal is
- Zhu, Dan,Chang, Denghu,Shi, Lei
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supporting information
p. 7180 - 7183
(2015/04/27)
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- General and practical formation of thiocyanates from thiols
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A new method for the cyanation of thiols and disulfides using cyanobenziodoxol(on)e hypervalent iodine reagents is described. Both aliphatic and aromatic thiocyanates can be accessed in good yields in a few minutes at room temperature starting from a broad range of thiols with high chemioselectivity. The complete conversion of disulfides to thiocyanates was also possible. Preliminary computational studies indicated a low energy concerted transition state for the cyanation of the thiolate anion or radical. The developed thiocyanate synthesis has broad potential for various applications in synthetic chemistry, chemical biology and materials science.
- Frei, Reto,Courant, Thibaut,Wodrich, Matthew D.,Waser, Jerome
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supporting information
p. 2662 - 2668
(2015/02/05)
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- Practical access to aromatic thiocyanates by CuCN-mediated direct aerobic oxidative cyanation of thiophenols and diaryl disulfides
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The practical and mild aerobic oxidative CuCN-mediated cyanation of thiophenols and diaryl disulfides was investigated. The reaction was performed in air at room temperature and reached aromatic thiocyanates in moderate to good yields starting from a broad range of diversely functionalized substrates.
- Castanheiro, Thomas,Gulea, Mihaela,Donnard, Morgan,Suffert, Jean
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p. 7814 - 7817
(2015/02/19)
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- Copper-catalyzed cyanation of disulfides by azobisisobutyronitrile leading to thiocyanates
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The copper-catalyzed cyanation of disulfides by azobisisobutyronitrile (AIBN) was developed, leading to thiocyanates in moderate to good yields. This procedure tolerates a series of functional groups, such as chloro, nitro, methyl and methoxycarbonyl in the phenyl ring of disulfides. Notably, it enables the use of two ArS units in (ArS)2. CuI was found to be essential for the in situ formation of cyanide anions. This journal is
- Teng, Fan,Yu, Jin-Tao,Yang, Haitao,Jiang, Yan,Cheng, Jiang
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p. 12139 - 12141
(2014/12/11)
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- Synthesis of aryl thiocyanates via copper-catalyzed aerobic oxidative cross-coupling between arylboronic acids and KSCN
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A new protocol for the preparation of aryl thiocyanates by the cross-coupling reaction of arylboronic acids with KSCN salt is described. The coupling reaction was catalyzed by 20 mol% of copper acetate in the presence of 2.0 equivalents 4-methylpyridine serving both as ligand and base under 0.2 MPa of molecular oxygen. A variety of arylboronic acids, including those with substituents at ortho position, were suitable under the reaction conditions. Georg Thieme Verlag Stuttgart · New York.
- Sun, Nan,Zhang, Han,Mo, Weimin,Hu, Baoxiang,Shen, Zhenlu,Hu, Xinquan
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supporting information
p. 1443 - 1447
(2013/07/26)
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- One-pot catalyst-free synthesis of β-and γ-hydroxy sulfides using diaryliodonium salts and microwave irradiation
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A simple and rapid one-pot protocol is described for the preparation of α- and β-hydroxy sulfides. The direct solvent-free microwave irradiation of diaryliodonium salts, potassium thiocyanate, and ethylene glycol/β-propylene glycol without any catalyst or base affords the final compounds in good yields (65-95 %) in around 10-25 min. Copyright
- Vaddula, Buchi Reddy,Varma, Rajender S.,Leazer, John
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p. 6852 - 6855
(2013/02/22)
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- Efficient and novel method for thiocyanation of aromatic compounds using trichloroisocyanuric acid/ammonium thiocyanate/wet SiO2
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An efficient and novel method for thiocyanation of aromatic and heteroaromatic compounds using trichloroisocyanuric acid/ammonium thiocyanate/wet SiO2 is described. Copyright Taylor & Francis Group, LLC.
- Akhlaghinia, Batool,Pourali, Ali-Reza,Rahmani, Marzieh
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experimental part
p. 1184 - 1191
(2012/04/04)
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- Synthesis of aryl thiocyanates using Al2O3/MeSO 3H (AMA) as a novel heterogeneous system
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Indoles and various aromatic and heteroaromatic compounds undergo smooth thiocyanation with ammonium thiocyanate in the presence of a mixture of Al 2O3, MeSO3H (AMA) under mild conditions without use of any organic solvent
- Hosseini-Sarvari, Mona,Tavakolian, Mina
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experimental part
p. 318 - 321
(2009/04/16)
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- Catalytic thiocyanation of aryldiazonium salts in the presence of copper salts
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Aryldiazonium fluoroborates readily react with potassium thiocyanate in the presence of the CuI/CuII/Phen catalytic system to give arylthiocyanates in high yields.
- Beletskaya, Irina P.,Sigeev, Alexander S.,Peregudov, Alexander S.,Petrovskii, Pavel V.
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p. 250 - 251
(2007/10/03)
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- Improved procedure to aryl thiocyanates: A new synthetic application of dry arenediazonium o-benzenedisulfonimides
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Aryl thiocyanates 3 (22 examples) were easily prepared by reaction of dry arenediazonium o-benzenedisulfonimides 1 and sodium thiocyanate (2) in anhydrous acetonitrile at room temperature (20-25 °C) in the presence of copper powder (Procedure A) and at 50 °C or room temperature without the metal catalyst (Procedure B). The yields were from very good to excellent in Procedure A (average yield = 83%), and from modest to excellent in Procedure B (average yield = 63%). In comparison with the thiocyanod-ediazoniation carried out under traditional Sandmeyer-type conditions, the yields of 3 were higher and the isothiocyanate isomers were formed only in traces. Moreover, the results obtained in the absence of copper confirm the role of the anion of salts 1 as an electron transfer agent.
- Barbero,Degani,Diulgheroff,Dughera,Fochi
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p. 585 - 590
(2007/10/03)
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- An efficient synthetic route to aryl thiocyanates from arenesulfinates
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An efficient procedure for the conversion ot the inexpensive and readily available arenesulfinate (sodium) salts in three steps into the corresponding aryl thiocyanates is described. Overall yields are high, and the presence of both electron-with drawing and electron-donating substituents is well tolerated.
- Still,Watson
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p. 1355 - 1359
(2007/10/03)
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- Reactions of arenediazonium tetrafluoroborates with inorganic and organic salts
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Arenediazonium tetrafluoroborates were reacted with inorganic and organic salts under anionarylation reaction conditions in the presence of strong nucleophiles (O,O-dimetyl dithiophosphate, N,N-diethyldithiocarbamate, and O-alkyl dithiocarbonate anions) and in the absence of catalysts [Cu(I) and Fe(II) salts] to obtain in high yields (dimethoxythiophosphinoylmercapto)-, (N,N-diethylthiocarbamoylmercapto)-, and (alkoxythiocarbonylmercapto)benzenes. The products of the reactions of arenediazonium tetrafluoroborates with potassium thiocyanate were identified and their compositions were determined. These reactions are proposed to occur by a radical mechanism, both under catalytic and noncatalytic conditions.
- Grishchuk,Gorbovoi,Zagrichuk,Ganushchak,Kudrik
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p. 1299 - 1303
(2007/10/03)
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- A new preparative method of thiocanates by the solid state thiosulfonate/cyanide reaction
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The mixing and heating of thiosulfonates with potassium cyanide in the solid state gave a variety of thiocyanates in good yield. This method provides easy access to aryl thiocyanates.
- Fujiki, Kiyoko,Yoshida, Eiji
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p. 3289 - 3294
(2007/10/03)
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- Thiocyanatoarylation of α,β,β-Trifluorostyrene
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Reactions of α,β,β-trifluorostyrene with arenediazonium tetrafluoroborates and potassium thiocyanate result in addition of the aryl and thiocyanato group across the double bond. Unlike other related reactions, the process requires no catalyst. The reaction is accompanied by formation of aryl thiocyanates and aryl isothiocyanates as by-products.
- Bilaya,Obushak,Ganushchak
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p. 995 - 998
(2007/10/03)
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- Syntheses of Organic N,N-Dialkyldithiocarbamates or Organic Thiocyanates from Organozincs and Corresponding Thio-Anions via the Inversion of Electronic Reactivity of the Anions with NCS-Oxidation
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Novel displacement of metal ions from organometallic compounds with nucleophilic reagents was achieved in the reaction between organozinc compounds and N,N-dialkyldithiocarbamate ions (N,N-DAD-) or thiocyanate ion by the assistance of NCS, whereby alkyl or aryl N,N-DAD or alkyl, alkenyl, alkynyl, aryl, or heteroaryl thiocyanates were obtained in moderate to excellent yields as the result of novel bond construction between carbon fragments from organozinc compounds and thio-anions.
- Takagi, Kentaro,Takachi, Hideaki,Sasaki, Ken
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p. 6552 - 6556
(2007/10/03)
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- THIOCYANOARYLATION OF VINYL AND VINYLIDENE CHLORIDES
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A method was developed for the preparation of chlorine-containing aliphatic-aromatic thicyanates (1-chloro- and 1,1-dichloro-1-thiocyanato-2-arylethanes) by reactions of arenediazonium tetrafluoroborates with vinyl chloride and with vinylidene chloride in presence of potassium (sodium or ammonium) thocyanate.A necessary condition for success in the reaction is the presence of a catalyst: Cu(II) or Fe(II) thicyanate.
- Grishchuk, B. D.,Gorbovoi, P. M.,Kudrik, E. Ya.,Ganushchak, N. I
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p. 2396 - 2401
(2007/10/02)
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- N3-(ARYLTHIO-, ARALKYLTHIO- AND ALKYLTHIO)-5,5-DIMETHYLHYDANTOINS: SULFENYL GROUP TRANSFER REACTIONS AND THEIR PROPERTIES
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Sulfenyl-transfer reactions toward a variety of nucleophiles were successfully carried out using N3-sulfenyl-substituted 5,5-dimethylhydantoins (2a-c).During the course of the synthesis of 2 by the reaction of N1-bromo-5,5-dimethylhydantoin (1c) with disulfides, the sulfenyl groups were found to be at the position of N3 although the bromine was at N1 in the starting monobromohydantoin (1c).Some mechanistic speculations were considered for the formation of 2 from 1c.
- Takeda, Ken'ichi,Horiki, Kusuo
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p. 367 - 373
(2007/10/02)
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- THE REACTION BETWEEN ARENEDIAZONIUM TETRAFLUOROBORATES AND ALKALINE THICARBOXYLATES IN DMSO: A CONVENIENT ACCESS TO ARYL THIOLESTERS AND OTHER AROMATIC SULFUR DERIVATIVES.
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The reaction between potassium thioacetate or sodium thiobenzoate and arenediazonium tetrafluoroborates in DMSO leads to the corresponding aryl thiolesters 1 which can either be isolated or further reacted providing a convenient one-pot access to a number of other aromatic sulfur derivatives.
- Petrillo, Giovanni,Novi, Marino,Garbarino, Giacomo,Filiberti, Marcos
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p. 7411 - 7420
(2007/10/02)
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- Facile Synthesis of Thiocyanate Using Trimethylsilyl Cyanide
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Arenethiocyanate can be prepared by reaction of trimethylsilyl cyanide with sodium arenesulphinate or arenesulphonyl chloride.
- Kagabu, Shinzo,Maehara, Masaki,Sawahara, Keisuke,Saito, Katsuhiro
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p. 1485 - 1486
(2007/10/02)
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- Reaction of Aryl Aldehydes with Thiocyanates in the Presence of Tributylphosphine
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Aryl aldehydes react with methyl thiocyanate in the presence of tributylphosphine to afford S-methyl thiobenzoates and arylacetonitriles in good yields.This is a novel disproportionation reaction involving carbon-carbon bond formation.These compounds thus obtained are easily converted into deoxybenzoins using sodium hydride.On the other hand, p-dialkylaminobenzaldehydes react with methyl thiocyanate under the same conditions to furnish both the corresponding trans-dicyanostilbenes and succinonitriles in moderate yields.Finally, the reaction was carried out with aryl thiocyanates resulting in the formation of addition products.
- Yokoyama, Masataka,Ohteki, Hiroko,Kurauchi, Masahiko,Hoshi, Kazuko,Yanagisawa, Eizaburo,et al.
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p. 2635 - 2640
(2007/10/02)
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- Boron Trifluoride as a Cyclodehydrating Agent: Synthesis of Aryl Thiocyanates via Pyrylium Tetrafluoroborates
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5,6-Dihydro-2,4-diphenylnaphthopyrylium thiocyanate (5) has been prepared in excellent yield.It reacts with primary arylamines to yield the corresponding pyridinium thiocyanates (6) in yields 60percent, which can undergo solvolysis in chlorobenzene
- Elshafie, Sayed Mahmoud M.
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- SYNTHESIS OF ARYL THIOCYANATES FROM ARYL ALKYL SULPHIDES. CONVERSION OF UNACTIVATED ARYL HALIDES INTO ARYL THIOCYANATES
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Aryl alkyl sulphides, easily obtained from aryl halides, can be selectively dealkylated in HMPA by treatment with sodium, sodium methanethiolate or sodium methoxide.The resulting solutions, containing the sodium arenethiolates, when treated with BrCN or ICN, afford the corresponding aryl thiocyanates in moderate to good yields.A by-product is obtained in several cases to whom the structure of ArSP(O)(NMe2)2 has been attributed.
- Testaferri, L.,Tingoli, M.,Tiecco, M.,Chianelli, D.,Montanucci, M.
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p. 263 - 268
(2007/10/02)
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- NEW METHODS AND REAGENTS IN ORGANIC SYNTHESIS. 23. DIETHYL PHOSPHOROCYANIDATE(DEPC): A USEFUL REAGENT FOR AN UNPRECEDENTED TRANSFORMATION OF SULFINIC ACIDS TO THIOCYANATES
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Diethyl phosphorocyanidate(DEPC) can be efficiently used for a simple, one-step transformation of sulfinic acids to thiocyanates.
- Harusawa, Shinya,Shioiri, Takayuki
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p. 447 - 448
(2007/10/02)
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- Se-Phenyl Areneselenosulfonates: Their Facile Formation and Striking Chemistry
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Benzeneseleninic acid reacts rapidly at 0 deg C with aromatic sulfinic acids according to the stoichiometry of eq 3 to form Se-phenyl arenesulfonates, PhSeSO2Ar (2), in high yield.In contrast to thiosulfonates, PhSSO2Ar, areneselenosulfonates are extremely photosensitive and undergo quite rapid photodecomposition.The principal products of this photodecomposition are the sulfonic anhydride, ArSO2OSO2Ar, and diphenyl diselenide.In the presence of added alkenes the facile photodissociation of 2 can be used to initiate a free-radical chain reaction that results in the addition of 2 to the alkene to form β-phenylseleno sulfones in good yield.The β-phenylseleno sulfones can be converted to synthetically useful α,β-unsaturated sulfones by oxidation of the β-phenylseleno group to the corresponding selenoxide and subsequent elimination of PhSeOH.Photoaddition of 2 to 2,5-norbornadiene to 5-(phenylseleno)-exo-3-nortricyclyl aryl sulfone as the almost exclusive product, while photoaddition to 1,5-cyclooctadiene gives a mixture of approximately equal amounts of the 1,2-adduct, 5-(phenylseleno)-6-arenesulfonyl-1-cyclooctene, and the product of transannular addition, 6-(phenylseleno)-exo-2-arenesulfonyl-cis-bicyclooctane.Besides their extraordinary ease of photodissociation, compounds 2 also react extremely readily with nucleophiles: Nu- + PhSeSO2Ar -> PhSeNu + ArSO2-.Kinetic studies show that the reactivity of PhSeSO2Ar with cyanide ion in such a reaction is 70000 times larger than the reactivity of the corresponding thiosulfonate, PhSSO2Ar.
- Gancarz, Roman A.,Kice, John L.
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p. 4899 - 4906
(2007/10/02)
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- POSSIBILITY OF USING ANTIMONY PENTAFLUORIDE INTERCALATED IN GRAPHITE AS CATALYSTS FOR REACTIONS OF THE FRIEDEL-CRAFTS TYPE
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Antimony pentafluoride intercalated in graphite, produced by the reaction of gaseous antimony pentafluoride with powdered graphite in a flow-type system at 140-160 deg C, exhibits the characteristics of liquid antimony pentafluoride in the temperature range of 50-100 deg C and can be used as a catalyst for various processes of the Friedel-Crafts type.The alkylation (by 1-bromooctane, cyclohexene, cyclopentene, and acylation by capryloyl, benzoyl, and perfluorobutyryl chlorides) of benzene were realized.The oxidative characteristics of antimony pentafluoride were used for the generation of the polyatomic doubly charged sulfur cation and electrophilic reagents from polyfluorodiaryl disulfide, lead thiocyanate, and mercuric oxide and their introduction into reaction with benzene.
- Gurin, G. G.,Avramenko, A. A.,Nikonorov, Yu. I.,Yakobson, G. G.
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p. 1340 - 1345
(2007/10/02)
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- Effect of Solvation on the Nucleophilic Reaction of Stable Carbanions with Diaryl Disulfides
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Stable carbanions react with diaryl disulfides in aqueous solution by direct displacement (SN2) reaction to yield an arylthiol anion and the corresponding sulfide as products.The reaction of 1,3-dicarbonyl carbanions with 5,5'-dithiobis(2-nitrobenzoic acid) is characterized by Broensted βC value of 0.5.Nitroalkane carbanions react 102-104 slower than 1,3-dicarbonyl carbanions of the same pK and are correlated by a Broensted βC of 0.95.The second-order rate constants for the reaction of nitroalkane carbanions increase by factors of 104-106 as the solvent is changed from water to dimethyl sulfoxide.Smaller increases are observed in the rate constants for reaction of 2,4-pentadienone carbanion (102) and malonitrile carbanion (100.6) with the same sulfide.A linear correlation is found between log (kMe2SO4/kHOH) and the increase in pK for the carbon acid ionization on changing the solvent from water to dimethyl sulfoxide.The effect is attributed to large differences in ground-state carbanion solvation which are reduced or absent in the transition state.Parallels are drawn between the nucleophilic reaction of stable carbanions with diaryl disulfides and proton-transfer reactions of the same carbanions.
- Gilbert, H. F.
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p. 7059 - 7065
(2007/10/02)
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- Heterocycles in Organic Synthesis. Part 36. An Alternative to the Gattermann Reaction for the Conversion of Anilines into Thiocyanates
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5,6-Dihydro-2,4-diphenylnaphthopyrylium thiocyanate is prepared in high yield.It reacts with primary arylamines to yield the corresponding fused pyridinium thiocyanates which when pyrolysed with a KNCS-NaCNS eutectic at ca. 220 deg C give the aryl thiocyanates in yields averaging 80percent.
- Katritzky, Alan R.,Thind, Sukhpal S.
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p. 865 - 868
(2007/10/02)
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