6738-04-1Relevant articles and documents
Ligand- and Counterion-Assisted Phenol O-Arylation with TMP-Iodonium(III) Acetates
Kikushima, Kotaro,Miyamoto, Naoki,Watanabe, Kazuma,Koseki, Daichi,Kita, Yasuyuki,Dohi, Toshifumi
supporting information, p. 1924 - 1928 (2022/03/27)
High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate for phenol O-arylation was achieved. It was first determined that the TMP ligand and acetate anion cooperatively enhance the electrophilic reactivity toward phenol oxygen atoms. The proposed method provides access to various diaryl ethers in significantly higher yields than the previously reported techniques. Various functional groups, including aliphatic alcohol, boronic ester, and sterically hindered groups, were tolerated during O-arylation, verifying the applicability of this ligand- and counterion-assisted strategy.
Diaryl Ether Formation Merging Photoredox and Nickel Catalysis
Liu, Le,Nevado, Cristina
supporting information, p. 2188 - 2193 (2021/05/04)
Photoredox and Ni catalysis are combined to produce diaryl ethers under mild conditions. A broad range of aryl halides and phenol derivatives are cross-coupled in the presence of a readily available organic photocatalyst and NiBr2(dtbpy). Symmetrical diaryl ethers have also been directly obtained from aryl bromides in the presence of water. Mechanistic investigations support the involvement of Ni(0) species at the outset of the reaction and a Ni(II)/Ni(III)-photocatalyzed single electron transfer process preceding the productive C(sp2)-OAr reductive elimination.
Competing Pathways in O-Arylations with Diaryliodonium Salts: Mechanistic Insights
Stridfeldt, Elin,Lindstedt, Erik,Reitti, Marcus,Blid, Jan,Norrby, Per-Ola,Olofsson, Berit
supporting information, p. 13249 - 13258 (2017/09/12)
A mechanistic study of arylations of aliphatic alcohols and hydroxide with diaryliodonium salts, to give alkyl aryl ethers and diaryl ethers, has been performed using experimental techniques and DFT calculations. Aryne intermediates have been trapped, and additives to avoid by-product formation originating from arynes have been found. An alcohol oxidation pathway was observed in parallel to arylation; this is suggested to proceed by an intramolecular mechanism. Product formation pathways via ligand coupling and arynes have been compared, and 4-coordinated transition states were found to be favored in reactions with alcohols. Furthermore, a novel, direct nucleophilic substitution pathway has been identified in reactions with electron-deficient diaryliodonium salts.
Nickel-Catalyzed Deamidative Step-Down Reduction of Amides to Aromatic Hydrocarbons
Dey, Aniruddha,Sasmal, Sheuli,Seth, Kapileswar,Lahiri, Goutam Kumar,Maiti, Debabrata
, p. 433 - 437 (2017/06/05)
To date, cleavage of the C-N bond in aromatic amides has been achieved in molecules with a distorted constitutional framework around the nitrogen atom. In this report, a nickel-catalyzed reduction of planar amides to the corresponding lower hydrocarbon homologue has been reported. This involves a one-pot reductive cleavage of the C-N bond followed by a tandem C-CO bond break in the presence of a hydride source. Substrate scope circumscribes deamidation examples which proceed via oxidative addition of nickel in the amide bonds of nontwisted amides. Mechanistic studies involving isolation and characterization of involved intermediates via different spectroscopic techniques reveal a deeper introspection into the plausible catalytic cycle for the methodology.
The Suzuki-Miyaura Coupling of Nitroarenes
Yadav, M. Ramu,Nagaoka, Masahiro,Kashihara, Myuto,Zhong, Rong-Lin,Miyazaki, Takanori,Sakaki, Shigeyoshi,Nakao, Yoshiaki
supporting information, p. 9423 - 9426 (2017/07/24)
Synthesis of biaryls via the Suzuki-Miyaura coupling (SMC) reaction using nitroarenes as an electrophilic coupling partners is described. Mechanistic studies have revealed that the catalytic cycle of this reaction is initiated by the cleavage of the aryl-nitro (Ar-NO2) bond by palladium, which represents an unprecedented elemental reaction.
Visible-light-mediated synthesis of diaryl ethers from arylboronic acids and diaryliodonium salts
Liu, Li,Tang, Jiaqi,Qiang, Jian,Li, Jian,He, Mingyang
, p. 261 - 264 (2016/07/06)
With visible-light irradiation, a simple and metal-free photocatalytic system for the synthesis of diaryl ethers from arylboronic acids and diaryliodonium salts has been developed. The reaction proceeded in high yield for a range of different substrates in the presence of eosin Y under mild reaction conditions.
General method for functionalized polyaryl synthesis via aryne intermediates
Truong, Thanh,Mesgar, Milad,Le, Ky Khac Anh,Daugulis, Olafs
supporting information, p. 8568 - 8576 (2014/07/07)
A method for base-promoted arylation of arenes and heterocycles by aryl halides and aryl triflates is described. Additionally, in situ electrophilic trapping of ArLi intermediates generated in the reaction of benzyne with deprotonated arenes or heterocycles has been developed, providing rapid and easy access to a wide range of highly functionalized polyaryls. Base-promoted arylation methodology complements transition-metal-catalyzed direct arylation and allows access to structures that are not easily accessible via other direct arylation methods. The reactions are highly functional-group tolerant, with alkene, ether, dimethylamino, trifluoromethyl, ester, cyano, halide, hydroxyl, and silyl functionalities compatible with reaction conditions.
Synthesis of benzannulated heterocycles by twofold Suzuki-Miyaura couplings of cyclic diarylborinic acids
Dimitrijevic, Elena,Cusimano, Madeline,Taylor, Mark S.
supporting information, p. 1391 - 1394 (2014/03/21)
Two-fold Suzuki-Miyaura cross-couplings of cyclic diarylborinic acids are described. This novel annulation method enables the synthesis of benzo-fused heterocycles from dihaloarenes or gem-dibromoolefins.
Reactions of enantiopure cyclic diols with sulfuryl chloride
Boyd, Derek R.,Sharma, Narain D.,Kaik, Magdalena,McIntyre, Peter B.A.,Malone, John F.,Stevenson, Paul J.
, p. 2128 - 2136 (2014/03/21)
Monocyclic allylic cis-1,2-diols reacted with sulfuryl chloride at 0 °C in a regio- and stereo-selective manner to give 2-chloro-1-sulfochloridates, which were hydrolysed to yield the corresponding trans-1,2-chlorohydrins. At -78 °C, with very slow addition of sulfuryl chloride, cyclic sulfates were formed in good yields, proved to be very reactive with nucleophiles and rapidly decomposed on attempted storage. Reaction of a cyclic sulfate with sodium azide yielded a trans-azidohydrin without evidence of allylic rearrangement occurring. An enantiopure bicyclic cis-1,2-diol reacted with sulfuryl chloride to give, exclusively, a trans-1,2-dichloride enantiomer with retention of configuration at the benzylic centre and inversion at the non-benzylic centre; a mechanism is presented to rationalise the observation.
Solar energy assisted synthesis of palladium nanoplates and its application in 2-phenoxy-1,1′-biphenyls and N,N-dimethyl-[1,1′-biphenyl] derivatives synthesis
Patil, Aniruddha B.,Bhanage, Bhalchandra M.
, p. 30 - 37 (2013/09/12)
Present work aims to develop a greener approach for the palladium nanoplates (PdNPs) synthesis and its catalytic applications. The protocol deals with solar energy assisted ionic palladium reduction in the presence of polyvinylpyrrolidone (PVP) and ethylene glycol (EG) with a good shape selectivity. Polyvinylpyrrolidone plays a duel role of capping agent and mild reductant; whereas, ethylene glycol acts as a reductant and solvent. The optimum sunlight concentration is a key factor to the anticipated nanoplate's synthesis. Results show that the most of nanoparticles are hexagonal and triangular nanoplates in the range of 20-50 nm. This is a first report which shows ~70% selectivity to the nanoplates formation using sun light. The study also covers it's catalytic application, wherein; 2-phenoxy-1,1′- biphenyls and N,N-dimethyl-[1,1′-biphenyl] derivatives were synthesized by a simple, ligand free, faster, one pot, ecological and economic protocol in aqueous medium. The catalyst shows better performance than that of conventionally available 10% Pd/C catalyst. The prepared PdNPs showed excellent catalytic performance to the desired products with recyclability.