16336-45-1Relevant academic research and scientific papers
Mechanistic insight into the pyridine enhanced α-selectivity in alkyne hydrothiolation catalysed by quinolinolate-rhodium(I)-N-heterocyclic carbene complexes
Palacios, Laura,Di Giuseppe, Andrea,Artigas, María José,Polo, Victor,Lahoz, Fernando J.,Castarlenas, Ricardo,Pérez-Torrente, Jesús J.,Oro, Luis A.
, p. 8548 - 8561 (2016)
RhI-NHC-olefin complexes bearing a N,O-quinolinolate bidentate ligand have been prepared from [Rh(μ-OH)(NHC)(η2-olefin)]2 precursors (olefin = cyclooctene, ethylene). The disposition of the chelate ligand with regard to the carbene i
Catalytic conversion of alkynes to α-vinyl sulfides mediated by carbene-linker-carbene (CXC) rhodium and iridium complexes
Tolley, Lewis C.,Fernández, Israel,Bezuidenhout, Daniela I.,Guisado-Barrios, Gregorio
, p. 516 - 523 (2021/02/09)
The catalytic activity of a set of mono- and bimetallic Rh(i) and Ir(i) complexes bearing carbene-linker-carbene (CXC) bis-triazolylidene ligands (with X = O, N) coordinated in a bridging or chelating fashion was evaluated in the hydrothiolation of alkyne
In Situ Prepared Solar Light-Driven Flexible Actuated Carbon Cloth-Based Nanorod Photocatalyst for Selective Radical–Radical Coupling to Vinyl Sulfides
Singh, Chandani,Yadav, Rajesh K.,Kim, Tae Wu,Upare, Pravin P.,Gupta, Abhishek Kumar,Singh, Atul P.,Yadav, Bal Chandra,Dwivedi, Dilip K.
, p. 955 - 962 (2021/03/31)
A global challenge faced by light harvesting photocatalyst is how to promote the selective organic transformation, such as C-S bond formation via radical–radical coupling under solar light. Here, we report a two-dimensional covalent organic frameworks (2D-COFs), poly (perylene-imide-benzoquinone) nanorod through in?situ condensation on flexible activated carbon cloth (PPIBNR-FACC) to function as a light harvester material for highly selective radical–radical coupling to vinyl sulfides (i.e. C-S bond activation). Such a structure supports charge transfer from PPIBNR to FACC, which is essential for the selective radical–radical coupling. Hence, organic transformation is attaining high yields and selectivity (?99%) under solar light using in?situ prepared PPIBNR-FACC photocatalyst. The structural virtues of PPIBNR-FACC will trigger the utmost investigations into designable and versatile 2D-COFs for fine chemical synthesis.
Solar light active flexible activated carbon cloth-based photocatalyst for Markovnikov-selective radical-radical cross-coupling of S-nucleophiles to terminal alkyne and liquefied petroleum gas sensing
Singh, Pooja,Yadav, Rajesh K.,Kim, Tae Wu,Yadav, Tara C.,Gole, Vitthal,Gupta, Abhishek K.,Singh, Kuldeep,Kumar, Kuldeep,Yadav, Bal Chandra,Dwivedi
, p. 1435 - 1444 (2021/04/05)
Selective radical-radical coupling of terminal alkynes and thiol has been broadly used in chemical synthesis, providing plausible entries to the formation of anti-Markovnikov products. Because of the selective control and Kharasch effect, the formation of Markovnikov products still remains an immense challenge. Herein, we designed a covalent organic polymer, poly(naphthalene 1,4,5,8-tetracarboxylic dianhydrideimide-benzoquinone) through in situ polymerization on activated flexible carbon cloth to function as a light harvester material for selective Markovnikov radical-radical coupling of terminal alkynes and thiol. Mechanistic explorations verified that cross-coupling between radical of terminal alkynes and thiol might be the key route in this organic transformation, such as C—S bond formation. This selective radical-radical Markovnikov of cross-coupling protocol provide an opportunity to assist the synthesis of valuable vinyl sulfide. Additionally, the synthesized material has been explored as liquefied petroleum gas (LPG) sensor for 0.5, 1.0, 1.5, and 2.0?vol% LPG, respectively. At 2.0?vol% LPG, it shows maximum sensor response as 635.29. Least response and recovery times are 2.44 and 1.0?s, respectively.
Selectivity control in thiol-yne click reactions: Via visible light induced associative electron upconversion
Ananikov, Valentine P.,Burykina, Julia V.,Gordeev, Evgeniy G.,K?nig, Burkhard,Shlapakov, Nikita S.
, p. 10061 - 10070 (2020/10/13)
An associative electron upconversion is proposed as a key step determining the selectivity of thiol-yne coupling. The developed synthetic approach provided an efficient tool to access a comprehensive range of products-four types of vinyl sulfides were prepared in high yields and selectivity. We report practically important transition-metal-free regioselective thiol-yne addition and formation of the demanding Markovnikov-type product by a radical photoredox process. The photochemical process was directly monitored by mass-spectrometry in a specially designed ESI-MS device with green laser excitation in the spray chamber. The proposed reaction mechanism is supported by experiments and DFT calculations. This journal is
Umpolung Difunctionalization of Carbonyls via Visible-Light Photoredox Catalytic Radical-Carbanion Relay
Wang, Shun,Cheng, Bei-Yi,Sr?en, Matea,K?nig, Burkhard
supporting information, p. 7524 - 7531 (2020/08/05)
The combination of photoredox catalysis with the Wolff-Kishner (WK) reaction allows the difunctionalization of carbonyl groups by a radical-carbanion relay sequence (photo-Wolff-Kishner reaction). Photoredox initiated radical addition to N-sulfonylhydrazones yields α-functionalized carbanions following the WK-type mechanism. With sulfur-centered radicals, the carbanions are further functionalized by reaction with electrophiles including CO2 and aldehydes, whereas CF3 radical addition furnishes a wide range of gem-difluoroalkenes through β-fluoride elimination of the generated α-CF3 carbanions. More than 80 substrate examples demonstrate the broad applicability of this reaction sequence. A series of investigations including radical inhibition, deuterium labeling, fluorescence quenching, cyclic voltammetry, and control experiments support the proposed radical-carbanion relay mechanism.
Structural elucidation of supported Rh complexes derived from RhCl(PPh3)3 immobilized on surface-functionalized SBA-15 and their catalytic performance for C-heteroatom (S, O) bond formation
Yang, Yong,Chang, Ji Wong,Rioux, Robert M.
, p. 43 - 54 (2018/07/03)
The local structures of rhodium complexes derived from the immobilization of Wilkinson's complex, RhCl(PPh3)3, on SBA-15 silica functionalized with primary–amine, secondary–amine, or diphenylphosphine groups within the mesoporous channels were characterized by a series of techniques including XRD, HR-TEM, multinuclear (13C/29Si/31P) solid-state NMR, 2D 31P{1H} HETCOR NMR, XPS, and Rh K-edge EXAFS. Immobilization of RhCl(PPh3)3 through covalent bond formation with different functional groups grafted to the silica surface lead to variations in the local structure of the Rh center that has important implications for catalysis. The immobilized Rh complexes demonstrated high activity for the addition of alkynes with thiols (hydrothiolation) or sulfonic acids (hydrosulfonation) with excellent regio- and stereoselectivity under mild reaction conditions. This work demonstrates the elucidation of the local structure of the immobilized Rh complexes requires a complimentary multi-technique characterization approach that probes both the metal center itself and surrounding ligands.
General Synthesis of Alkenyl Sulfides by Palladium-Catalyzed Thioetherification of Alkenyl Halides and Tosylates
Velasco, Noelia,Virumbrales, Cintia,Sanz, Roberto,Suárez-Pantiga, Samuel,Fernández-Rodríguez, Manuel A.
supporting information, p. 2848 - 2852 (2018/05/29)
The cross-coupling reaction of alkenyl bromides with thiols catalyzed by palladium complexes derived from inexpensive dppf ligand is reported. These reactions occur under low catalyst loading and in high yields and display wide scope, including the coupling of bulky thiols and trisubstituted bromoolefins, and functional group tolerance. In addition, the thioetherification of less reactive chloroalkenes and, for the first time, alkenyl tosylates was accomplished using a catalyst generated from CyPFtBu alkylbisphosphine ligand.
Design of highly selective alkyne hydrothiolation RhI-NHC catalysts: Carbonyl-triggered nonoxidative mechanism
Palacios, Laura,Meheut, Yoann,Galiana-Cameo, María,Artigas, María José,DI Giuseppe, Andrea,Lahoz, Fernando J.,Polo, Victor,Castarlenas, Ricardo,Pérez-Torrente, Jesús J.,Oro, Luis A.
, p. 2198 - 2207 (2017/06/19)
New RhI-IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-carbene) complexes bearing an N,O-pyridine-2-methanolato (N-O) bidentate ligand have been prepared. The carbonyl complex Rh(N-O)(IPr)(CO) efficiently catalyzes the hydrothiolation of
A Hemilabile and Cooperative N-Donor-Functionalized 1,2,3-Triazol-5-Ylidene Ligand for Alkyne Hydrothiolation Reactions
Strydom, Ian,Guisado-Barrios, Gregorio,Fernández, Israel,Liles, David C.,Peris, Eduardo,Bezuidenhout, Daniela I.
supporting information, p. 1393 - 1401 (2017/02/05)
A series of novel cationic and neutral Rh complexes with an N-donor-functionalized 1,2,3-triazol-5-ylidene (TRZ) ligand (in which the pendant N donor is NHBoc, NH2, or NMe2) is described. The catalytic activity of these complexes was
