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All total 70 Articles be foundA facile and sustainable protocol to the preparation of aryl iodides using stable arenediazonium bis(trifluoromethylsulfonyl)imide salts via the telescopic process
Khaligh, Nader Ghaffari
, (2018)
The preparation of aryl iodides in a telescopic reaction using tert-butyl nitrite as a diazotization reagent and a mixture of bis(trifluoromethane) sulfonamide and glacial acetic acid as a mild acidic agent in ethanol followed by iododediazoniation with tetraethylammonium iodide in water was investigated. The current method has other advantages such as minimized waste by avoiding solvent for the purification of products in diazotization step, simple experimental procedure, and good yield of the sterically hindered aryl amines, metal and strong acid-free waste and environmentally benign conditions. The noteworthy features of this study are the preparation of stable arenediazonium bis(trifluoromethylsulfonyl)imide salts that can be used with no significant loss activity after 1?week and bis(trifluoromethane)sulfonamide was recovered in high yields from reactions.
Nitrite ionic liquid as a new reagent for in situ synthesis of aryl iodides and azides
Eshghi, Hossein,Bakavoli, Mehdi,Ghasemzadeh, Marjan
, p. 3999 - 4007 (2013)
A new ionic liquid, 1-methyl-3-(2-[2-(1-methyl-1H-imidazol-3-ium-3-yl)ethyloxy] ethyl)-1H-imidazol-3-ium dinitrite, was synthesized. This ionic liquid was used as a convenient nitrosonium source in diazotization of aryl amines into their corresponding diazonium salts, which were converted into aryl iodides and aryl azides using potassium iodide or sodium azide, respectively. Various aryl amines possessing electron-withdrawing groups or electron-donating groups were converted into the corresponding aryl iodides and aryl azides in excellent yields. Advantages of this methodology are the use of mild reaction conditions, short reaction times, and avoiding the use of toxic solvents.
PREPARATION OF AROMATIC IODIDES FROM BROMIDES VIA THE REVERSE HALOGEN EXCHANGE
Suzuki, Hitomi,Kondo, Akiko,Ogawa, Takuji
, p. 411 - 412 (1985)
Aromatic bromides undergo halogen exchange reaction with iodide ion in the presence of copper(I) iodide in hot hexamethylphosphoric triamide, to give the corresponding iodides in good to moderate yields.
The Reactivity of α-Fluoroketones with PLP Dependent Enzymes: Transaminases as Hydrodefluorinases
García-Ramos, Marina,Cuetos, Aníbal,Kroutil, Wolfgang,Grogan, Gideon,Lavandera, Iván
, p. 3967 - 3972 (2021/08/09)
A chemical method for the treatment of harmful halogenated compounds that has recently become of interest is the reductive dehalogenation of carbon-halogen bonds. In the case of a fluorine atom, this process is called hydrodefluorination. While many transition metal-based approaches now exist to reductively defluorinate aromatic fluoroarenes, the cleavage of C?F bonds in aliphatic compounds is not so well-developed. Here we propose a biocatalytic approach exploiting a promiscuous activity exhibited by transaminases (TAs). Hence, a series of α-fluoroketones have been defluorinated with excellent conversions using Chromobacterium violaceum and Arthrobacter sp. TAs under mild conditions and in aqueous medium, using a stoichiometric amount of an amine (e. g. 2-propylamine) as reagent and formally releasing its oxidized form (e. g. acetone), with ammonia and hydrogen fluoride as by-products. It is also demonstrated that this process can be performed in a regio- or stereoselective fashion.
Selective electrochemical oxidation of aromatic hydrocarbons and preparation of mono/multi-carbonyl compounds
Li, Zhibin,Zhang, Yan,Li, Kuiliang,Zhou, Zhenghong,Zha, Zhenggen,Wang, Zhiyong
, p. 2134 - 2141 (2021/09/29)
A selective electrochemical oxidation was developed under mild condition. Various mono-carbonyl and multi-carbonyl compounds can be prepared from different aromatic hydrocarbons with moderate to excellent yield and selectivity by virtue of this electrochemical oxidation. The produced carbonyl compounds can be further transformed into α-ketoamides, homoallylic alcohols and oximes in a one-pot reaction. In particular, a series of α-ketoamides were prepared in a one-pot continuous electrolysis. Mechanistic studies showed that 2,2,2-trifluoroethan-1-ol (TFE) can interact with catalyst species and generate the corresponding hydrogen-bonding complex to enhance the electrochemical oxidation performance. [Figure not available: see fulltext.]
Facile preparation of 5-alkyl-1-aryltetrazoles with arenes, acyl chlorides, hydroxylamine, and diphenylphosphoryl azide
Shibasaki, Kaho,Togo, Hideo
, p. 1816 - 1830 (2020/11/19)
Successive treatment of arenes with acyl chlorides and AlCl3, the addition of water and removal of solvent, the reaction with NH2OH?HCl and K2CO3, and the reaction with diphenylphosphoryl azide and DBU under warming conditions gave the corresponding 5-alkyl-1-aryltetrazoles efficiently in good to moderate yields. The present method is one-pot transformation of arenes into 5-alkyl-1-aryltetrazoles using the Friedel-Crafts acylation and the Beckmann rearrangement under transition-metal-free conditions.
