19013-30-0Relevant academic research and scientific papers
Palladium-Catalyzed Cyclobutanation of Aryl Sulfonates through both C-O and C-H Cleavage
Zhang, Liangwei,Liu, Long,Huang, Tianzeng,Dong, Qizhi,Chen, Tieqiao,Chen, Tieqiao
, p. 2189 - 2196 (2020/06/05)
A palladium-catalyzed cyclobutanation of aryl sulfonates with strained alkenes has been developed. The methodology is featured to achieve the cleavage of both C-O and C-H bonds of phenol derivatives in one pot. Under the reaction conditions, in addition t
Chromatography-Free and Eco-Friendly Synthesis of Aryl Tosylates and Mesylates
Lei, Xiangyang,Jalla, Anusha,Abou Shama, Mhd A.,Stafford, Jamie M.,Cao, Billy
supporting information, p. 2578 - 2585 (2015/09/01)
Two chromatography-free and eco-friendly protocols have been developed to synthesize aryl tosylates and mesylates by the tosylation and mesylation of the corresponding hydroxyarenes, respectively. These protocols are superior to other known ones regarding
Cyanation of unactivated aryl chlorides and aryl mesylates catalyzed by palladium and hemilabile MOP-type ligands
Tu, Yahui,Zhang, Yi,Xu, Sheng,Zhang, Zhaoguo,Xie, Xiaomin
supporting information, p. 2938 - 2942 (2015/01/16)
Palladium-catalyzed cyanation of aryl halides and pseudo halides with potassium hexacyanoferrate is described employing the hemilabile, bulky, and electron-rich MOP-type ligands. When the mixture of t-BuOH and H2O was used as the solvent and K2CO3 as the base, the MOP-type ligands showed high efficiency for the palladium-catalyzed cyanation. The effect of ligand structure was studied in detail, and 2-di-tert-butylphosphino-2′-isopropoxy-1,1′-binaphthyl was the more effective for the cyanation. The catalyst system allows the cyanation of unactivated aryl chlorides, and even aryl mesylates to occur in good yields. Furthermore, the reactivity of different arylated reagents in the catalytic system was found to be: ArBr > ArCl >> ArOMs > ArOSO2Im > ArOSO2NMe2.
Palladium-catalyzed intra-and intermolecular C-H arylation using mesylates: Synthetic scope and mechanistic studies
Ferguson, Devin M.,Rudolph, Stacey R.,Kalyani, Dipannita
, p. 2395 - 2401 (2014/07/21)
This paper describes the development of Pd-catalyzed inter-and intramolecular direct arylation using mesylates. Furthermore, a sequential mesylation/arylation protocol using phenols as substrates is described. These transformations are general with respect to the electronics of the C-H substrates and allow for the synthesis of diverse heterocyclic motifs in good yields. Both arenes and heteroarenes efficiently participate in these reactions. Preliminary mechanistic studies are presented for both inter-and intramolecular arylations.
Mechanistic insight into the formal [1,3]-migration in the thermal claisen rearrangement
Hou, Shili,Li, Xinyao,Xu, Jiaxi
, p. 10856 - 10869 (2013/02/23)
The thermal formal [1,3]-sigmatropic shift of allyl aryl ethers has been studied in depth experimentally with the aid of the density functional theory (DFT) calculations of the B3LYP function. Three mechanistic possibilities, referred to as the radical, ionic, and concerted mechanisms, have previously been put forth to explain the thermal [1,3]-rearrangement process. However, the intercrossing and radical trapping experiments indicate the rearrangement is an intramolecular process. The computational studies reveal that the concerted C[1,3]-sigmatropic shift suffered from a higher energetic barrier to allow the rearrangement to proceed under the conditions used. However, a tandem O[1,3]-sigmatropic shift with a configuration inversion of the oxygen atom and [3,3]-sigmatropic shift (the Claisen rearrangement) is the most likely pathway for the formal [1,3] rearrangement. Furthermore, the rearrangement experiments with a designed optically active substrate and O[1,3]-sigmatropic shift examples verify the new cascade rearrangement. In addition, computational and experimental studies indicate that water molecule assists the proton shift during the isomerization. The combined methods provide the new insight into the mechanism of the thermal formal [1,3]-migration in the Claisen rearrangement and the novel O[1,3]-sigmatropic shift as well.
Scope of direct arylation of fluorinated aromatics with aryl sulfonates
Chang, Joyce Wei Wei,Chia, Eugene Yurong,Chai, Christina Li Lin,Seayad, Jayasree
supporting information; experimental part, p. 2289 - 2299 (2012/04/10)
The scope and limitations of direct arylation of fluorinated aromatics with aryl sulfonates was examined. Pd(OAc)2, in the presence of MePhos and KOAc in THF, efficiently catalyzed the direct arylation of fluoro aromatics with aryl triflates un
Nickel catalyzed cross-coupling of aryl C-O based electrophiles with aryl neopentylglycolboronates
Leowanawat, Pawaret,Zhang, Na,Percec, Virgil
experimental part, p. 1018 - 1025 (2012/03/22)
The efficiency of mesylates, sulfamates, esters, carbonates, carbamates, and methyl ethers as C-O-based electrophiles attached to the 1- or 2-position of naphthalene and to activated and nonactivated phenyl substrates was compared for the first time in Ni-catalyzed cross-coupling with phenyl neopentylglycolboronates containing electron-rich and electron-deficient substituents in their para-position. These experiments were performed in the presence of four different Ni(II)- and Ni(0)-based catalysts. Ni(II)-based catalysts mediate the cross-coupling of most 2-naphthyl C-O electrophiles with both arylboronic acids and with neopentylglycolboronates when K 3PO4 is used as base. The same catalysts are not efficient when CsF is used as base. However, Ni(0)-based catalysts exhibit selective efficiency, and when reactive, their efficiency is higher than that of Ni(II)-based catalysts in the presence of both K3PO4 and CsF. These results provide both reaction conditions for the cross-coupling, and for the elaboration of orthogonal cross-coupling methodologies of various C-O based electrophiles with aryl neopentylglycolboronates. With the exception of mesylates and sulfamates the efficiency of all other 2-naphthyl C-O electrophiles was lower in cross-coupling with aryl neopentylglycolboronates than with arylboronic acids
Nickel-catalyzed C-P coupling of aryl mesylates and tosylates with H(O)PR1R2
Shen, Chaoren,Yang, Guoqiang,Zhang, Wanbin
supporting information; body text, p. 3500 - 3505 (2012/05/20)
A method was developed for the nickel-catalyzed phosphonylation of aryl mesylates and tosylates with H(O)PR1R2. To the best of our knowledge, this is the first example of nickel-catalyzed C-P coupling of aryl mesylates and tosylates. Most of the substrates gave moderate to good yields under our catalytic system.
Palladium-catalyzed borylation of aryl mesylates and tosylates and their applications in one-pot sequential suzuki-miyaura biaryl synthesis
Chow, Wing Kin,So, Chau Ming,Lau, Chak Po,Kwong, Fuk Yee
supporting information; experimental part, p. 6913 - 6917 (2011/08/03)
Top of the one-pots! The first palladium-catalyzed borylation of aryl tosylates and mesylates is described. The reaction conditions are mild and provide excellent functional-group compatibility (e.g., R=CN, CHO, COOMe, C(O)R, NH2, or NH-indole; see scheme). Pd/MeO-CM-phos allows one-pot sequential reactions in the preparation of unsymmetrical biaryls. Copyright
Neopentylglycolborylation of aryl mesylates and tosylates catalyzed by Ni-based mixed-ligand systems activated with Zn
Wilson, Daniela A.,Wilson, Christopher J.,Moldoveanu, Costel,Resmerita, Ana-Maria,Corcoran, Patrick,Hoang, Lisa M.,Rosen, Brad M.,Percec, Virgil
supporting information; experimental part, p. 1800 - 1801 (2010/04/24)
(Chemical Presented) The mixed-ligand system NiCl2(dppp)/dppf is shown to be an effective catalyst for the neopentylglycolborylation of ortho-, meta-, and para-substituted electron-rich and electrondeficient aryl mesylates and tosylates. The ad
