2267-25-6Relevant academic research and scientific papers
Fluorinations of unsymmetrical diaryliodonium salts containing: Ortho -sidearms; Influence of sidearm on selectivity
Abudken, Ahmed M. H.,Hope, Eric G.,Singh, Kuldip,Stuart, Alison M.
, p. 6140 - 6146 (2020/10/30)
Activated aromatics were reacted with two different fluoroidoane reagents 1 and 2 in the presence of triflic acid to prepare only the para-substituted diaryliodonium salts. With fluoroiodane 1 the unsymmetrical diaryliodonium salts contained an ortho-propan-2-ol sidearm, whereas the alcohol sidearm was eliminated to form an ortho-styrene sidearm in the reaction with fluoroiodane 2. Only the diaryliodonium salts containing a styrene sidearm were fluorinated successfully to deliver para-fluorinated aromatics in good yields.
Silver-mediated fluorination of potassium aryltrifluoroborates with Selectfluor Dedicated to Professor Andrea Vasella on the occasion of his 71st birthday
Dubbaka, Srinivas Reddy,Narreddula, Venkateswara Reddy,Gadde, Satyanarayana,Mathew, Thresen
, p. 9676 - 9681 (2015/01/08)
A simple and practical procedure for the silver-mediated fluorination of aryl- and heteroaryltrifluoroborates with electrophilic fluorine from Selectfluor and LiOH·H2O is presented. The reaction procedure is simple and easy to set up, the process produces fluorinated arenes and heteroarenes in good to excellent yields and a wide range of electronically and structurally diverse substrates are tolerated.
Iodine(I) reagents in hydrochloric acid-catalyzed oxidative iodination of aromatic compounds by hydrogen peroxide and iodine
Bedrac, Leon,Iskra, Jernej
, p. 1243 - 1248 (2013/06/27)
Hydrochloric acid activates the oxidative iodination of aromatic compounds with the iodine- hydrogen peroxide system through the formation of an iodine(I) compound as the iodinating reagent. Activation with hydrochloric acid is more powerful than that with sulfuric acid. The formation of dichloroiodic(I) acid (HICl2) with various forms of hydrogen peroxide was followed using UV spectroscopy. The HICl2 was used as the iodinating reagent. In the preparative oxidative iodinaton of various aromatic compounds, hydrochloric acid was used in a catalytic amount and the iodine(I) reagent was formed in situ with 0.5 equiv. hydrogen peroxide and 0.5 equiv. molecular iodine. Two types of reactivity were observed in oxidative iodination with iodine(I) species catalyzed by hydrochloric acid: in the iodination of anisole 1a better yields of iodination were observed with a smaller amount of hydrochloric acid, while on the contrary 4-tert-butyltoluene 1b gave better yields of iodination upon increasing the amount of hydrochloric acid. Reactivity was further manipulated by the choice of the solvent (MeCN, trifluoroethanol, hexafluoro-2-propanol). Copyright
Syntheses and herbicidal activity of pyrazolyl benzoxazole derivatives
Xue, Na,Zhou, Yuhan,Wang, Guowei,Miao, Weirong,Qu, Jingping
scheme or table, p. 15 - 21 (2010/05/03)
(Chemical Equation Presented) In recent years, protoporphyrinogen oxidase (Protox) inhibitor herbicides are developed rapidly, because of this type of herbicides shows high herbicidal activity and low toxicity. In this paper, we prepared a series of new substituted pyrazolyl benzoxazole derivative, which were synthesized from 4-fluorophenol, via a serial of reactions included chlorination, acylation, condensation, ring closure, methylation, nitration, and so on. All the structures are confirmed by 1H NMR, MS and element analysis. Preliminary bioassay shows that most substituted pyrazolyl benzoxazole derivatives exhibit high herbicidal activity to the tested gramineous weeds and latifoliate weeds.
Chlorination of aromatics with trichloroisocyanuric acid (TCICA) in bronsted-acidic imidazolium ionic liquid [BMIM(SO3H)][OTf]: An economical, green protocol for the synthesis of chloroarenes
Hubbard, Abigail,Okazaki, Takao,Laali, Kenneth K.
, p. 923 - 927 (2008/03/17)
A survey study on electrophilic chlorination of aromatics with trichloroisocyanuric acid (TCICA) in Bronsted-acidic imidazolium ionic liquid [BMIM(SO3H)][OTf] is reported. The reactions are performed under very mild conditions (at ～50°C) and give good to excellent yields, depending on the substrates. Chemoselectivity for mono- v. dichlorination can be tuned by changing the arene-to-TCICA ratio and the reaction time. The survey study and competitive experiments suggest that triprotonated/protosolvated TCICA is a selective/moderately reactive transfer-chlorination electrophile. Density functional theory was used as guide to obtain further insight into the nature of the chlorination electrophile and the transfer-chlorination step. CSIRO 2007.
Process for electrophilic aromatic substitution
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, (2008/06/13)
Processes for the electrophilic substitution of aromatic compounds, such as alkylation, with a desired substituent are disclosed. The processes include contacting the aromatic compound, a precursor of the desired substituent and an aqueous reagent containing zinc halide at elevated temperatures such as above 50° C.
Formation of Nonaromatic Products in the Chlorination of Simple Substituted Aromatic Ethers
Watson, William David
, p. 5270 - 5276 (2007/10/02)
The neat chlorination of 4-chloroanisole produces 1,3,4,5,6-pentachloro-4-methoxycyclohexene in 35percent yield.Mono- and dichlorinated anisoles and a variety of simple substituted anisoles were chlorinated to determine the generality of nonaromatic product formation. 3,4-Dichloroanisole, 4-fluoroanisole, 4-bromoanisole, 4-methylanisole, and 4-chlorophenetole form similar products based on their spectral properties.These products are proposed to form by a cis-1,2-chlorine addition followed by rapid cis-1,4 chlorine addition.On the basis of the NMR data, a predominate configuration is proposed.
