- Site-Selective Acceptorless Dehydrogenation of Aliphatics Enabled by Organophotoredox/Cobalt Dual Catalysis
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The value of catalytic dehydrogenation of aliphatics (CDA) in organic synthesis has remained largely underexplored. Known homogeneous CDA systems often require the use of sacrificial hydrogen acceptors (or oxidants), precious metal catalysts, and harsh reaction conditions, thus limiting most existing methods to dehydrogenation of non- or low-functionalized alkanes. Here we describe a visible-light-driven, dual-catalyst system consisting of inexpensive organophotoredox and base-metal catalysts for room-temperature, acceptorless-CDA (Al-CDA). Initiated by photoexited 2-chloroanthraquinone, the process involves H atom transfer (HAT) of aliphatics to form alkyl radicals, which then react with cobaloxime to produce olefins and H2. This operationally simple method enables direct dehydrogenation of readily available chemical feedstocks to diversely functionalized olefins. For example, we demonstrate, for the first time, the oxidant-free desaturation of thioethers and amides to alkenyl sulfides and enamides, respectively. Moreover, the system's exceptional site selectivity and functional group tolerance are illustrated by late-stage dehydrogenation and synthesis of 14 biologically relevant molecules and pharmaceutical ingredients. Mechanistic studies have revealed a dual HAT process and provided insights into the origin of reactivity and site selectivity.
- Zhou, Min-Jie,Zhang, Lei,Liu, Guixia,Xu, Chen,Huang, Zheng
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p. 16470 - 16485
(2021/10/20)
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- Electrophilic Vinylation of Thiols under Mild and Transition Metal-Free Conditions
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The iodine(III) reagents vinylbenziodoxolones (VBX) were employed to vinylate a series of aliphatic and aromatic thiols, providing E-alkenyl sulfides with complete chemo- and regioselectivity, as well as excellent stereoselectivity. The methodology displays high functional group tolerance and proceeds under mild and transition metal-free conditions without the need for excess substrate or reagents. Mercaptothiazoles could be vinylated under modified conditions, resulting in opposite stereoselectivity compared to previous reactions with vinyliodonium salts. Novel VBX reagents with substituted benziodoxolone cores were prepared, and improved reactivity was discovered with a dimethyl-substituted core.
- Castoldi, Laura,Di Tommaso, Ester Maria,Gr?fen, Barbara,Olofsson, Berit,Reitti, Marcus
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supporting information
p. 15512 - 15516
(2020/06/23)
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- A Simplified Protocol for the Stereospecific Nickel-Catalyzed C-S Vinylation Using NiX 2 Salts and Alkyl Phosphites
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A Ni-catalyzed C-S cross-coupling using only NiI 2 (0.5-2.5 molpercent) and P(O i Pr) 3 (2.0-10.0 molpercent) is reported. Using an air-stable Ni(II) precatalyst, and a cheap and commercially available ligand, a scalable and robust method was developed to cross-couple various thiophenols and styryl bromides, including some sterically encumbered thiols, an α-bromocinnamaldehyde as well as a thiolation-cyclization.
- Larin, Egor M.,Lautens, Mark,Marchese, Austin D.,Mirabi, Bijan
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p. 311 - 319
(2019/12/28)
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- Alkenyl preparation method of sulfide
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The invention discloses a method for preparing alkenyl sulfide. The method comprises the following steps: adding a styrene derivative of the formula I as shown in the specification into a disulfide compound of the formula II as shown in the specification,
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Paragraph 0062-0064
(2017/03/23)
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- Acid/Phosphide-Induced Radical Route to Alkyl and Alkenyl Sulfides and Phosphonothioates from Sodium Arylsulfinates in Water
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A newly developed aqueous system with acid and phosphide was introduced in which odorless and stable sodium arylsulfinates can in situ generate arylsulfenyl radicals. These radicals have high reactivity to react with alkynes, alkenes, and H-phosphine oxides for the synthesis of alkyl and alkenyl sulfides and phosphonothioates. The control experiments and quantum calculations are also performed to gain insights into the generation mechanism of arylsulfenyl radicals. Notably, the chemistry is free of thiol odors, organic solvents, and metals.
- Lin, Ya-Mei,Lu, Guo-Ping,Wang, Gui-Xiang,Yi, Wen-Bin
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p. 382 - 389
(2017/04/26)
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- Stereoselective Synthesis of Alkenyl Silanes, Sulfones, Phosphine Oxides, and Nitroolefins by Radical C-S Bond Cleavage of Arylalkenyl Sulfides
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A radical-mediated approach has been introduced for the C-S bond activation of arylalkenyl sulfides. The protocol provides an efficient approach for the generation of various alkenes including alkenyl silanes, sulfones, phosphine oxides, and nitroolefins. In most cases, these radical substitutions are performed under metal-free conditions with stereospecificity.
- Lin, Ya-mei,Lu, Guo-ping,Wang, Rong-kang,Yi, Wen-bin
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supporting information
p. 1100 - 1103
(2017/03/15)
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- Sulfamic acid: An efficient and recyclable catalyst for the regioselective hydrothiolation of terminal alkenes and alkynes with thiols
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Herein, we described a new method for the preparation of thioethers through hydrothiolation of alkenes and alkynes, using sulfamic acid as a reusable catalyst. Generally, this new methodology afforded the desired products in very good yields, under metal
- Rosa, Clarissa Helena,Peixoto, Maura Luise B.,Rosa, Gilber Ricardo,Godoi, Benhur,Galetto, Fábio Zazyki,D'Oca, Marcelo Gon?alves Montes,Godoi, Marcelo
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supporting information
p. 3777 - 3781
(2017/09/09)
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- Copper-mediated stereospecific C-H oxidative sulfenylation of terminal alkenes with disulfides
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A copper and iodine-mediated C-H oxidative sulfenylation of olefins with diaryl disulfides has been developed for the stereospecific synthesis of vinyl thioether. With the combination of Cu(OTf)2 and I2, a variety of terminal alkenes
- Tu, Hai-Yong,Hu, Bo-Lun,Deng, Chen-Liang,Zhang, Xing-Guo
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supporting information
p. 15558 - 15561
(2015/10/28)
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- Highly stereoselective anti-Markovnikov hydrothiolation of alkynes and electron-deficient alkenes by a supported Cu-NHC complex
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A practical, efficient, and low-cost heterogeneous catalyst consisting of a Cu-NHC (N-heterocyclic carbene) complex grafted to SBA-15 silica for the catalytic hydrothiolation of alkynes and electron-deficient alkenes under mild reaction conditions has been developed. The heterogeneous catalyst displays higher activity and stereoselectivity to Z-anti-Markovnikov isomers compared with the homogeneous analog under otherwise identical reaction conditions. The catalytic system is applicable to a broad range of alkynes and thiols and is recyclable without significant loss in catalytic performance. High activity and perfect selectivity to alkyl sulfides formed by the addition of electron-deficient alkenes to various thiols catalyzed by the supported Cu-NHC complex were also realized. This journal is the Partner Organisations 2014.
- Yang, Yong,Rioux, Robert M.
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p. 3916 - 3925
(2014/08/05)
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- Stereoselective formation of Z- or E-vinyl thioethers from arylthiols and acetylenes under transition-metal-free conditions
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Vinyl sulfide formation with good yield and high regio- and stereoselectivities from thiols and acetylenes under transition-metal-free conditions is described. Potassium phosphate was used as an effective additive to enhance the reaction yield and selecti
- Liao, Yunfeng,Chen, Shanping,Jiang, Pengcheng,Qi, Hongrui,Deng, Guo-Jun
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p. 6878 - 6885
(2013/11/06)
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- Glycerol/CuI/Zn as a recyclable catalytic system for synthesis of vinyl sulfides and tellurides
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A convenient approach to the Cu-catalyzed coupling of diphenyl disulfide and diphenyl ditelluride with vinyl bromides using a recyclable catalytic system and glycerol as a green solvent is described. This protocol was efficiently used in the preparation of vinyl sulfides and vinyl tellurides with a variety of substituents in good yields and stereoselectively. The solvent/catalyst system was directly reused for four cycles without loss of activity.
- Gon?alves, Lóren C.C.,Lima, David B.,Borba, Pedro M.Y.,Perin, Gelson,Alves, Diego,Jacob, Raquel G.,Lenard?o, Eder J.
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p. 3475 - 3480
(2013/07/05)
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- Synthesis of vinyl sulfides under base-free conditions using selenium ionic liquid
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A very simple procedure is described for the efficient synthesis of vinyl sulfides by hydrothiolation of terminal alkynes using 1-n-butyl-3- methylimidazolium methylselenite, [bmim][SeO2(OCH3)]. The reaction proceeds cleanly under mi
- Thurow, Samuel,Ostosi, Naiana T.,Mendes, Samuel R.,Jacob, Raquel G.,Lenard?o, Eder J.
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experimental part
p. 2651 - 2653
(2012/06/30)
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- Heterogeneous hydrothiolation of alkynes with thiols catalyzed by diphosphino-functionalized MCM-41 anchored rhodium complex
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A novel diphosphino-functionalized MCM-41 anchored rhodium complex [MCM-41-2P-RhCl(PPh3)] was conveniently synthesized by the reaction of diphosphino-functionalized MCM-41 (MCM-41-2P) with RhCl(PPh3) 3. It was found that this rhodium complex is an efficient catalyst for the hydrothiolation of terminal alkynes with thiols and can be recovered and recycled by a simple filtration of the reaction solution and used for at least ten consecutive trials without any decreases in activity.
- Zhao, Hong,Peng, Jian,Cai, Mingzhong
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experimental part
p. 138 - 142
(2012/03/11)
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- Carbon dioxide mediated stereoselective copper-catalyzed reductive coupling of alkynes and thiols
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A simple protocol for the stereoselective copper-catalyzed hydrothiolation of alkynes under a CO2 atmosphere has been developed. The stereoselectivity is determined by the presence/absence of a CO2 atmosphere. The reaction system is robust and utilizes inexpensive, readily available substrates. A cyclic alkene/carboxylate copper complex intermediate is proposed as the key step in determining the stereoselectivity, and an equivalent amount of water is found to play an active role as a proton donor.
- Nurhanna Riduan, Siti,Ying, Jackie Y.,Zhang, Yugen
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supporting information; experimental part
p. 1780 - 1783
(2012/06/04)
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- Indium(iii) catalysed substrate selective hydrothiolation of terminal alkynes
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In(OTf)3 is reported as the first catalyst having the ability to selectively catalyse both Markovnikov and anti-Markovnikov hydrothiolation of terminal alkynes under identical reaction conditions depending upon the nature of the thiol employed.
- Sarma, Rupam,Rajesh, Nimmakuri,Prajapati, Dipak
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supporting information; experimental part
p. 4014 - 4016
(2012/06/01)
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- Highly regio- and stereoselective hydrothiolation of acetylenes with thiols catalyzed by a well-defined supported Rh complex
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Highly regio- and stereoselective hydrothiolation of a wide range of alkynes with various thiols was demonstrated in the presence of a well-defined Rh complex supported on mesoporous SBA-15 silica. The catalyst was easily recovered and reused several times without significant loss of activity or selectivity.
- Yang, Yong,Rioux, Robert M.
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supporting information; experimental part
p. 6557 - 6559
(2011/06/28)
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- Synthesis of vinyl sulfides by copper-catalyzed decarboxylative C-S cross-coupling
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A novel method for the synthesis of vinyl sulfides by the decarboxylative cross-coupling of arylpropiolic acids with thiols using copper(I) salts as catalysts has been developed. In the presence of CuI and Cs2CO 3, a variety of thiols reacted with arylpropiolic acids to afford the corresponding vinyl sulfides in good to excellent yields with high stereoselectivity for Z-isomers.
- Ranjit, Sadananda,Duan, Zhongyu,Zhang, Pengfei,Liu, Xiaogang
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supporting information; experimental part
p. 4134 - 4136
(2010/11/17)
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- Lanthanum-catalyzed stereoselective synthesis of vinyl sulfides and selenides
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Lanthanum oxide/TMEDA-catalyzed cross-coupling of vinyl halides with thiols/diphenyl diselenide in anhydrous DMSO and KOH is reported. Utilizing this protocol various vinyl sulfides and selenides were synthesized in excellent yields with retention of the stereochemistry. The catalyst was recyclable.
- Reddy, V. Prakash,Swapna,Kumar, A. Vijay,Rao, K. Rama
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experimental part
p. 293 - 296
(2010/03/26)
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- MnCl2·4H2O-catalyzed potential protocol for the synthesis of aryl/vinyl sulfides
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MnCl2 · 4H2O is described as an efficient catalytic system for the cross coupling of aryl/vinyl halides with thiols using KOH as base and DMSO as solvent. By using this new catalytic system various aryl/vinyl sulfides were synthesize
- Bandaru, Madhav,Sabbavarpu, Narayana Murthy,Katla, Ramesh,Yadavalli, Venkata Durga Nageswar
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supporting information; experimental part
p. 1149 - 1151
(2011/02/28)
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- Water-promoted regioselective hydrothiolation of alkynes
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Water promotes hydrothiolation of unactivated alkynes efficiently without any catalyst or additive. The reaction at room temperature furnishes vinyl sulfides with high regioselectivity via anti-Markovnikov addition. The terminal al- kynes provide dithiola
- Bhadra, Sukalyan,Ranu, Brindaban C.
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experimental part
p. 1605 - 1609
(2010/04/03)
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- Recyclable nano copper oxide catalyzed stereoselective synthesis of vinyl sulfides under ligand-free conditions
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A simple and efficient protocol for the cross-coupling of vinyl halides with thiols catalyzed by recyclable CuO nanoparticles under ligand-free conditions is reported. This methodology results in the synthesis of a variety of vinyl sulfides in excellent y
- Reddy, Vutukuri Prakash,Swapna, Kokkirala,Kumar, Akkilagunta Vijay,Rao, Kakulapati Rama
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experimental part
p. 2783 - 2788
(2010/03/03)
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- Ionic liquid promoted regio- And stereoselective addition of thiols to alkynes and alkenes under organic solvent free condition - A green reaction
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A simple ionic liquid, l-methyl-3-pentylimidazolium fluoroborate, [pmIm]BF4, promotes anti-Markovnikov addition of thiols to alkynes providing (Z)- and (E)-vinyl sulfides stereoselectively. The addition of thiols to alkenes in presence of another ionic liquid, [pmim]Br proceeds through anti-Markovnikov manner, whereas the addition to vinyl ethers and acetates occurs at more electrophilic C-2 position adjacent to oxygen. The products are obtained in high yields.
- Ranu, Brindaban C.,Chattopadhyay, Kalicharan,Ghosh, Sudip,Jana, Ranjan
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experimental part
p. 1199 - 1204
(2009/12/31)
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- Hydrothiolation of terminal alkynes with diaryl disulfides and diphenyl diselenide: selective synthesis of (Z)-1-alkenyl sulfides and selenides
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A simple, stereoselective and efficient method for the hydrothiolation of terminal alkynes with diaryl disulfides and diphenyl diselenide has been developed. In the presence of CuI, rongalite, and Cs2CO3, a variety of disulfides underwent the reaction of terminal alkynes stereoselectively to afford the corresponding (Z)-1-alkenyl sulfides in moderate to excellent yields. It is noteworthy that hydroselenations of 1,2-diphenyldiselane with alkynes are also conducted smoothly to afford (Z)-1-alkenyl selenides in good yields under the standard conditions.
- Wang, Zhang-Lin,Tang, Ri-Yuan,Luo, Pei-Song,Deng, Chen-Liang,Zhong, Ping,Li, Jin-Heng
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p. 10670 - 10675
(2008/12/23)
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- Stereoselective synthesis of E-vinyl sulfides from alkynes in water under neutral conditions using β-cyclodextrin
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This is the first example of stereoselective synthesis of E-vinyl sulfides in water in excellent yields by hydrothiolation of aromatic alkynes with thiophenols by anti-Markonikov addition in the presence of β-cyclodextrin. This protocol tolerates a wide v
- Sridhar,Surendra,Srilakshmi Krishnaveni,Srinivas,Rama Rao
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p. 3495 - 3497
(2007/10/03)
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