636-98-6Relevant articles and documents
Biaryl Coupling of Aryldiazonium Salts and Arylboronic Acids Catalysed by Gold
Medina-Mercado, Ignacio,Porcel, Susana
, (2022/03/15)
A gold-catalysed coupling of aryldiazonium salts with arylboronic acids is described. The reactions proceed in satisfactory yields under irradiation with blue LEDs in the presence of KF and a catalytic amount of ascorbic acid. Notably, 4-nitrobenzendiazonium tetrafluoroborate is sufficiently reactive to undergo the coupling with a variety of arylboronic acids in the absence of aryl radical initiators. The coupling is applicable for electron-donating and electron-withdrawing groups present at the para, ortho, and meta positions of both substrates.
Palladium-Catalyzed Decarbonylative Iodination of Aryl Carboxylic Acids Enabled by Ligand-Assisted Halide Exchange
Boehm, Philip,Cacherat, Bastien,Lee, Yong Ho,Martini, Tristano,Morandi, Bill
supporting information, p. 17211 - 17217 (2021/07/02)
We report an efficient and broadly applicable palladium-catalyzed iodination of inexpensive and abundant aryl and vinyl carboxylic acids via in situ activation to the acid chloride and formation of a phosphonium salt. The use of 1-iodobutane as iodide source in combination with a base and a deoxychlorinating reagent gives access to a wide range of aryl and vinyl iodides under Pd/Xantphos catalysis, including complex drug-like scaffolds. Stoichiometric experiments and kinetic analysis suggest a unique mechanism involving C?P reductive elimination to form the Xantphos phosphonium chloride, which subsequently initiates an unusual halogen exchange by outer sphere nucleophilic substitution.
σ-Bond initiated generation of aryl radicals from aryl diazonium salts
Chan, Bun,McErlean, Christopher S. P.,Nashar, Philippe E.,Tatunashvili, Elene
supporting information, p. 1812 - 1819 (2020/03/17)
σ-Bond nucleophiles and molecular oxygen transform aryl diazonium salts into aryl radicals. Experimental and computational studies show that Hantzsch esters transfer hydride to aryl diazonium species, and that oxygen initiates radical fragmentation of the diazene intermediate to produce aryl radicals. The operational simplicity of this addition-fragmentation process for the generation of aryl radicals, by a polar-radical crossover mechanism, has been illustrated in a variety of bond-forming reactions.
Low-temperature and highly efficient liquid-phase catalytic nitration of chlorobenzene with NO2: Remarkably improving the para-selectivity in O2-Ac2O-Hβ composite system
Deng, Renjie,Liu, Pingle,Luo, He'an,Ni, Wenjin,You, Kuiyi,Zhao, Fangfang
, (2020/02/26)
In this work, we developed a low-temperature and efficient approach for the highly selective preparation of valuable p-nitrochlorobenzene from the liquid-phase catalytic nitration of chlorobenzene with NO2 in O2-Ac2O-Hβ composite system. The results demonstrated that the introduction of molecular oxygen remarkably enhanced the chlorobenzene conversion and the cooperation catalysis of Hβ zeolite and Ac2O envidently improved the selectivity to para-nitro product. Under the optimized reaction conditions, 93.6 % of the selectivity to p-nitrochlorobenzene with 84.0 % of chlorobenzene conversion was obtained, and the ratio of p-nitrochlorobenzene to o-nitrochlorobenzene could reach up to 20.3. Furthermore, the selectivity distribution of nitration products was reasonably explained by the density functional theory (DFT) calculation. Finally, the possible nitration reaction pathway of chlorobenzene with NO2 was suggested in O2-Ac2O-Hβ composite catalytic system. The present work affords a new and mild nitration approach for highly selective preparation of valuable para-nitro products, and has potential industrial application prospects.
Arene diazonium saccharin intermediates: A greener and cost-effective alternative method for the preparation of aryl iodide
Ghaffari Khaligh, Nader,Rafie Johan, Mohd,Shahnavaz, Zohreh,Zaharani, Lia
, p. 535 - 542 (2020/06/01)
In the current protocol, the arene diazonium saccharin derivatives were initially produced from various substituted aromatic amines; subsequently, these intermediates were treated with a greener organic iodide for the preparation of the aryl iodide. We tried to choose low-cost, commercially available, biodegradable, recoverable, ecofriendly, and safe reagents and solvents. The arene diazonium saccharin intermediates could be stored in the liquid phase into a refrigerator for a long time with no significant loss activity. The outstanding merits of the current protocol (a) included the partial recovering of saccharin and tetraethylammonium salt, (b) reduce the use of solvents and the reaction steps due to eliminating separation and purification of intermediates, (c) good yield of the sterically hindered substrates, and (d) avoid the generation of heavy metal or corrosive waste.
Two-Phase Electrochemical Generation of Aryldiazonium Salts: Application in Electrogenerated Copper-Catalyzed Sandmeyer Reactions
Goljani, Hamed,Tavakkoli, Zahra,Sadatnabi, Ali,Nematollahi, Davood
supporting information, p. 5920 - 5924 (2020/08/12)
The electrochemical generation of aryldiazonium salts from nitroarenes in a two-phase system (ethyl acetate/water) was reported for the first time. Some compounds including azo, azosulfone, and arylazides were prepared in good yields with good purity. Cathodically generated aryldiazoniums and anodically produced copper(Ι) ions were used to perform Sandmeyer reactions. To improve the method, an H-type self-driving cell equipped with a Zn rod as an anode was introduced and used for two-phase aryldiazonium production.
N-Nitroheterocycles: Bench-Stable Organic Reagents for Catalytic Ipso-Nitration of Aryl- And Heteroarylboronic Acids
Budinská, Alena,Katayev, Dmitry,Passera, Alessandro,Zhang, Kun
supporting information, (2020/03/30)
Photocatalytic and metal-free protocols to access various aromatic and heteroaromatic nitro compounds through ipso-nitration of readily available boronic acid derivatives were developed using non-metal-based, bench-stable, and recyclable nitrating reagents. These methods are operationally simple, mild, regioselective, and possess excellent functional group compatibility, delivering desired products in up to 99% yield.
Dehydroxyalkylative halogenation of C(aryl)-C bonds of aryl alcohols
Liu, Mingyang,Zhang, Zhanrong,Liu, Huizhen,Wu, Tianbin,Han, Buxing
supporting information, p. 7120 - 7123 (2020/07/14)
We herein report Cu mediated side-directed dehydroxyalkylative halogenation of aryl alcohols. C(aryl)-C bonds of aryl alcohols were effectively cleaved, affording the corresponding aryl chlorides, bromides and iodides in excellent yields. Aryl alcohols could serve as both aromatic electrophilic and radical synthetic equivalents during the reaction.
Facile Access to Diverse Libraries of Internal Alkynes via Sequential Iododediazoniation/Decarboxylative Sonogashira Reaction in Imidazolium ILs without Ligand or Additive
Prabhala, Pavankumar,Savanur, Hemantkumar M.,Kalkhambkar, Rajesh G.,Laali, Kenneth K.
supporting information, p. 2061 - 2064 (2019/03/07)
Convenient access to diverse libraries of internal alkynes via decarboxylative Sonogashira reaction of alkynyl-carboxylic acids with iodoarenes, employing imidazolium-ILs as solvent, along with piperidine-appended imidazolium [PAIM][NTf2] as task-specific basic IL is demonstrated, without the need for any ligand or additive. The feasibility to perform these reactions by sequential one-pot iododediazoniation/decarboxylative Sonogashira reaction is also shown, and the scope of the methods is underscored by providing 29 examples. The potential for recycling and reuse of the IL solvent is also examined.
