- Decarboxylation with Carbon Monoxide: The Direct Conversion of Carboxylic Acids into Potent Acid Triflate Electrophiles
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We report a new strategy for the conversion of carboxylic acids into potent acid triflate electrophiles. The reaction involves oxidative carbonylation of carboxylic acids with I2 in the presence of AgOTf, and is postulated to proceed via acyl hypoiodites that react with CO to form acid triflates. Coupling this chemistry with subsequent trapping with arenes offers a mild, room temperature approach to generate ketones directly from broadly available carboxylic acids without the use of corrosive and reactive Lewis or Bronsted acid additives, and instead from compounds that are readily available, stable, and functional group compatible.
- Kinney, R. Garrison,Arndtsen, Bruce A.
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supporting information
p. 5085 - 5089
(2019/04/01)
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- Cyanation of unactivated aryl chlorides and aryl mesylates catalyzed by palladium and hemilabile MOP-type ligands
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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.
- Tu, Yahui,Zhang, Yi,Xu, Sheng,Zhang, Zhaoguo,Xie, Xiaomin
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supporting information
p. 2938 - 2942
(2015/01/16)
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- Palladium-catalyzed borylation of aryl mesylates and tosylates and their applications in one-pot sequential suzuki-miyaura biaryl synthesis
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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
- Chow, Wing Kin,So, Chau Ming,Lau, Chak Po,Kwong, Fuk Yee
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supporting information; experimental part
p. 6913 - 6917
(2011/08/03)
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- A general palladium catalyst system for suzuki-miyaura coupling of potassium aryltrifluoroborates and aryl mesylates
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(Figure presented) The first general examples of palladium-catalyzed Suzuki-type cross-coupling of aryl and heteroaryl mesylates with potassium aryl and heteroaryltrifluoroborates are presented. In addition to biaryl couplings, the cross-coupling reactions of aryl mesylates with alkyl and vinyltrifluoroborate salts have also been successfully accomplished.
- Chow, Wing Kin,So, Chau Ming,Lau, Chak Po,Kwong, Fuk Yee
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supporting information; experimental part
p. 5109 - 5112
(2010/09/05)
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- A mild and efficient palladium-catalyzed cyanation of aryl mesylates in water or tBuOH/water
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Cool and compatible: Aryl mesylates and tosylates underwent palladium-catalyzed cyanation under mild, aqueous conditions at 65-80°C (see scheme). In many cases, water could be used as the reaction medium without a cosolvent, and a variety of substituents R, such as keto, aldehyde, ester, free amine, and nitrile groups, remained intact during the transformation. Cy=cyclohexyl, Ms=methanesulfonyl, Ts=p-toluenesulfonyl.
- Yeung, Pui Yee,So, Chau Ming,Lau, Chak Po,Kwong, Fuk Yee
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supporting information; experimental part
p. 8918 - 8922
(2011/02/24)
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- Palladium-indolylphosphine-catalyzed hiyama cross-coupling of aryl mesylates
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(Chemical Equation Presented) Aryl mesylates are found to be applicable as electrophiles in organosilicon-mediated coupling reactions. The catalyst system comprising 2 mol % of Pd(OAc)2 and CM-phos supporting ligand is highly effective in catalyzing Hiyama cross-coupling of various aryl and heteroaryl mesylates. Interesting acid additive effects show that the presence of 0.25-0.50 equiv of acetic acid efficiently suppresses the mesylate decomposition and generally promotes the coupling product yields.
- So, Chau Ming,Lee, Hang Wai,Lau, Chak Po,Kwong, Fuk Yee
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supporting information; experimental part
p. 317 - 320
(2009/07/04)
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- A general palladium-catalyzed Suzuki-Miyaura coupling of aryl mesylates
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(Chemical Equation Presented) Catalyze this! The first palladium-catalyzed Suzuki-Miyaura coupling of unactivated aryl mesylates is reported, with not only arylboronic acids, but also other organoboron nucleophiles (see picture; Z=B(OH)2, BF3K, BPin). The reaction conditions are compatible with various common functional groups (R1=alkyl, OMe, CHO, CO, CN, CO2R′, heteroaryl).
- So, Chau Ming,Lau, Chak Po,Kwong, Fuk Yee
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supporting information; experimental part
p. 8059 - 8063
(2009/04/13)
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- CH3SO3H/P2O5 (4:1) as an efficient reagent for the one-pot synthesis of acylaryl methane sulfonates of phenolic
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Methansulfonic acid/di-phosphorus pentoxide (4:1) was found to be an efficient reagent for one-pot synthesis of acylaryl methane sulfonates of phenolic esters via Fries rearrangement. This method is easy, rapid, and high-yielding reactions for the synthesis of acylaryl methane sulfonates.
- Kaboudin
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p. 887 - 892
(2007/10/03)
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- Methanesulfonic acid/phosphorus oxychloride (MAPO) as a new efficient reagent in the fries rearrangement
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Methanesulfonic acid/phosphorus oxychloride (MAPO) was found to be a new efficient reagent in the Fries rearrangement of phenolic esters. Fries rearrangement of phenolic esters in the presence of MAPO, gave acylaryl methane sulfonates as major products.
- Kaboudin, Babak
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p. 12865 - 12872
(2007/10/03)
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