4521-08-8Relevant academic research and scientific papers
Biaryl synthesis via decarboxylative Pd-catalyzed reactions of arenecarboxylic acids and diaryliodonium triflates
Becht, Jean-Michel,Le Drian, Claude
, p. 3161 - 3164 (2008)
(Chemical Equation Presented) A novel simple and efficient synthesis of biaryls via a Pd-catalyzed decarboxylative cross-coupling reaction of arenecarboxylic acids and diaryliodonium triflates is described. The PdCl 2/DPEphos catalytic system in the presence of Ag2CO 3 in DMSO was found to be the most efficient. Various biaryls, including sterically hindered biaryls, were synthesized with yields ranging from 37 to 85%.
Room Temperature C-H Arylation of Benzofurans by Aryl Iodides
Mayhugh, Amy L.,Luscombe, Christine K.
supporting information, p. 7079 - 7082 (2021/09/18)
A robust method of room temperature direct arylation for benzofuran is reported. This discovery allows for mild arylation by commercially available aryl iodides with complete C-2 regioselectivity and tolerates a range of functional groups, including heat sensitive groups. Mechanistically, a Heck-type oxyarylation product from a direct arylation process is reported as a key piece of evidence for a carbopalladation intermediate.
Characterization of heterogeneous aryl-Pd(ii)-oxo clusters as active species for C-H arylation
Shin, Taeil,Kim, Minjun,Jung, Younjae,Cho, Sung June,Kim, Hyunwoo,Song, Hyunjoon
supporting information, p. 14404 - 14407 (2020/12/01)
C-H arylation with heterogeneous palladium was investigated. The surface oxidation of Pd nanoparticles with a hypervalent iodine reagent, [Ph2I]BF4, resulted in the generation of Pd(ii)-aryl-oxo clusters, which were characterized as the crucial intermediate.
Decarboxylative Suzuki-Miyaura coupling of (hetero)aromatic carboxylic acids using iodine as the terminal oxidant
Quibell, Jacob M.,Duan, Guojian,Perry, Gregory J.P.,Larrosa, Igor
supporting information, p. 6445 - 6448 (2019/06/07)
A novel methodology for the decarboxylative Suzuki-Miyaura-type coupling has been established. This process uses iodine or a bromine source as both the decarboxylation mediator and the terminal oxidant, thus avoiding the need for stoichiometric amounts of transition metal salts previously required. Our new protocol allows for the construction of valuable biaryl architectures through the coupling of (hetero)aromatic carboxylic acids with arylboronic acids. The scope of this decarboxylative Suzuki reaction has been greatly diversified, allowing for previously inaccessible non-ortho-substituted aromatic acids to undergo this transformation. The procedure also benefits from low catalyst loadings and the absence of stoichiometric transition metal additives.
Potassium tert-Butoxide-Mediated Condensation Cascade Reaction: Transition Metal-Free Synthesis of Multisubstituted Aryl Indoles and Benzofurans
Yang, Pengfei,Xu, Weiyan,Wang, Rongchao,Zhang, Min,Xie, Chunsong,Zeng, Xiaofei,Wang, Min
, p. 3658 - 3662 (2019/05/17)
An efficient and facile method to synthesize valuable disubstituted 2-aryl indoles and benzofurans in good yields has been demonstrated, based on a tert-butoxide-mediated condensation reaction involving a vinyl sulfoxide intermediate. Products are obtained from N- or O-benzyl benzaldehydes using dimethyl sulfoxide as a carbon source. The methodology features a wide functional group tolerance and transition metal-free environment. Preliminary mechanistic studies suggest that the reaction involves a tandem aldol reaction/Michael addition/dehydrosulfenylation/isomerization sequence through an ionic protocol.
Iridium-Catalyzed Aerobic Coupling of Salicylaldehydes with Alkynes: A Remarkable Switch of Oxacyclic Product
Yamane, Shintaro,Hinoue, Tomoaki,Usuki, Yoshinosuke,Itazaki, Masumi,Nakazawa, Hiroshi,Hayashi, Yoshihiro,Kawauchi, Susumu,Miura, Masahiro,Satoh, Tetsuya
supporting information, p. 7852 - 7855 (2018/05/08)
The iridium(III)/copper(II)-catalyzed dehydrogenative coupling of salicylaldehydes with internal alkynes proceeds efficiently under atmospheric oxygen through aldehyde C?H bond cleavage and decarbonylation. A variety of benzofuran derivatives can be synthesized by the environmentally benign procedure. DFT calculations suggest that this unique transformation involves the facile deinsertion of CO in the key metallacycle intermediate, which is in marked contrast to the corresponding rhodium(III) catalysis that leads to CO-retentive chromone derivatives.
Palladium-Catalyzed Regioselective C-2 Arylation of Benzofurans with N′-Acyl Arylhydrazines
Cao, Jun,Chen, Zi-Li,Li, Shu-Min,Zhu, Gao-Feng,Yang, Yuan-Yong,Wang, Cong,Chen, Wen-Zhang,Wang, Jian-Ta,Zhang, Ji-Quan,Tang, Lei
supporting information, p. 2774 - 2779 (2018/06/21)
A novel ligand-free palladium-catalyzed C-2 arylation of benzofurans has been developed using N′-acyl arylhydrazines as the coupling partners and TEMPO as an oxidant. This protocol features a wide functional-group tolerance and highly regioselective products with good to excellent yields.
A Ligand-Free Pt3Cluster Catalyzes the Markovnikov Hydrosilylation of Alkynes with up to 106Turnover Frequencies
Rivero-Crespo, Miguel A.,Leyva-Pérez, Antonio,Corma, Avelino
, p. 1702 - 1708 (2017/02/10)
The Pt-catalyzed hydrosilylation of alkynes is the procedure of choice to obtain vinylsilanes, and is claimed to be the most relevant application of Pt in organic synthesis. More than half a century after its discovery, only β-vinylsilanes (anti-Markovnikov addition) are obtained with simple Pt catalysts, whereas α-vinylsilanes (Markovnikov addition) remain elusive compounds. Here the catalysis of the Markovnikov hydrosilylation of terminal alkynes by Pt3clusters, in parts-per-million amounts, to give a wide variety of α-vinylsilanes in reasonable isolated yields and with turnover frequencies that can reach up to one million per hour is reported. Moreover, these α-vinylsilanes are reactive in well-stablished C?C bond-forming cascade reactions, in which the corresponding β-isomers are unreactive. Besides its efficiency and synthetic usefulness, this catalytic system is an excellent example of how the atom-by-atom aggregation of a catalytic metal leads to a different selectivity for a given reaction.
Transition-Metal-Free α-Arylation of Enolizable Aryl Ketones and Mechanistic Evidence for a Radical Process
Pichette Drapeau, Martin,Fabre, Indira,Grimaud, Laurence,Ciofini, Ilaria,Ollevier, Thierry,Taillefer, Marc
, p. 10587 - 10591 (2015/09/02)
The α-arylation of enolizable aryl ketones can be carried out with aryl halides under transition-metal-free conditions using KOtBu in DMF. The α-aryl ketones thus obtained can be used for step- and cost-economic syntheses of fused heterocycles and Tamoxifen. Mechanistic studies demonstrate the synergetic role of base and solvent for the initiation of the radical process.
Cascade Synthesis of 3-Alkylidene Dihydrobenzofuran Derivatives via Rhodium(III)-Catalyzed Redox-Neutral C-H Functionalization/Cyclization
Zhou, Zhi,Liu, Guixia,Chen, Yan,Lu, Xiyan
, p. 5874 - 5877 (2015/12/11)
An efficient rhodium(III)-catalyzed coupling reaction of N-phenoxyacetamides with propargyl carbonates to yield 3-alkylidene dihydrobenzofuran derivatives via C-H functionalization/cascade cyclization has been developed. This transformation represents a r
