633-99-8Relevant academic research and scientific papers
Activator free, expeditious and eco-friendly chlorination of activated arenes by N-chloro-N-(phenylsulfonyl)benzene sulfonamide (NCBSI)
Misal, Balu,Palav, Amey,Ganwir, Prerna,Chaturbhuj, Ganesh
supporting information, (2021/01/04)
N-Chloro-N-(phenylsulfonyl)benzene sulfonamide (NCBSI) has been explored for the first time as a chlorinating reagent for direct chlorination of various activated arenes and heterocycles without any activator. A comparative in-silico study was performed to determine the electrophilic character for NCBSI and commercially available N-chloro reagents to reveal the reactivity on a theoretical viewpoint. The reagent was prepared by an improved method avoiding the use of hazardous t-butyl hypochlorite. This reagent was proved to be very reactive compared to other N-chloro reagents. The precursor of the reagent N-(phenylsulfonyl)benzene sulfonamide was recovered from aqueous spent, which can be recycled to synthesize NCBSI. The eco-friendly protocol was equally applicable for the synthesis of industrially important chloroxylenol as an antibacterial agent.
Sulfoxide-Promoted Chlorination of Indoles and Electron-Rich Arenes with Chlorine as Nucleophile
Ji, Yuan-Zhao,Li, Hui-Jing,Wang, Yi-Ruo,Wu, Yan-Chao,Zhang, Zheng-Yan
supporting information, (2020/02/05)
An efficient chlorination of indoles and electron-rich arenes with chlorine anion as nucleophile is described. With the use of ethyl phenyl sulfoxide as the promoter, the reaction went smoothly under metal-free and mild conditions. Various indoles and electron-rich arenes are converted into the corresponding chlorinated compounds in moderate to excellent yields. A plausible interrupted Pummerer reaction mechanism was proposed without the oxidation of chloride anion. In addition, the byproduct thioether could be easily converted to the starting material sulfoxide just by a simple oxidation reaction. (Figure presented.).
Amplification of Trichloroisocyanuric Acid (TCCA) Reactivity for Chlorination of Arenes and Heteroarenes via Catalytic Organic Dye Activation
Rogers, David A.,Bensalah, Adam T.,Espinosa, Alvaro Tomas,Hoerr, John L.,Refai, Fares H.,Pitzel, Amy K.,Alvarado, Juan J.,Lamar, Angus A.
supporting information, p. 4229 - 4233 (2019/06/17)
Heteroarenes and arenes that contain electron-withdrawing groups are chlorinated in good to excellent yields (scalable to gram scale) using trichloroisocyanuric acid (TCCA) and catalytic Brilliant Green (BG). Visible-light activation of BG serves to amplify the electrophilic nature of TCCA, providing a mild alternative approach to acid-promoted chlorination of deactivated (hetero)aromatic substrates. The utility of the TCCA/BG system is demonstrated through comparison to other chlorinating reagents and by the chlorination of pharmaceuticals including caffeine, lidocaine, and phenazone.
Iodine(III)-Mediated, Controlled Di- or Monoiodination of Phenols
Satkar, Yuvraj,Yera-Ledesma, Luisa F.,Mali, Narendra,Patil, Dipak,Segura-Quezada, Luis A.,Ramírez-Morales, Perla I.,Solorio-Alvarado, César R.,Navarro-Santos, Pedro
, p. 4149 - 4164 (2019/04/30)
An oxidative procedure for the electrophilic iodination of phenols was developed by using iodosylbenzene as a nontoxic iodine(III)-based oxidant and ammonium iodide as a cheap iodine atom source. A totally controlled monoiodination was achieved by buffering the reaction medium with K3PO4. This protocol proceeds with short reaction times, at mild temperatures, in an open flask, and generally with high yields. Gram-scale reactions, as well as the scope of this protocol, were explored with electron-rich and electron-poor phenols as well as heterocycles. Quantum chemistry calculations revealed PhII(OH)·NH3 to be the most plausible iodinating active species as a reactive "I+" synthon. In light of the relevance of the iodoarene moiety, we present herein a practical, efficient, and simple procedure with a broad functional group scope that allows access to the iodoarene core unit.
Radical Truce-Smiles reactions on an isoxazole template: Scope and limitations
Rashid, Srood O.,Almadhhi, Sultan S.,Berrisford, David J.,Raftery, James,Vitorica-Yrezabal, Inigo,Whitehead, George,Quayle, Peter
, p. 2413 - 2430 (2019/03/23)
The use of TiCl3-HCl as promotor in the radical Truce-Smiles reactions of 2-(((3,5-dimethylisoxazol-4-yl)sulfonyl)oxy)benzenediazonium salts has been investigated in detail. During these reactions the desired Truce-Smiles rearrangement (via an ipso-substitution reaction) is accompanied by the formation of a number of by-products including dihydrobenzo[5,6][1,2]oxathiino[3,4-d]isoxazole 4,4-dioxides, dioxidobenzo[e][1,2]oxathiin-3-yl)ethan-1-ones, anilines and chloroaromatics. Replacing TiCl3-HCl by Cu(NO3)2-Cu2O as reductant in these reactions was found to afford broadly comparable product distributions. Competition and radical clock experiments also provide an indication of the relative susceptibility of the isoxazole nucleus towards attack by aryl radicals.
Ammonium Salt-Catalyzed Highly Practical Ortho-Selective Monohalogenation and Phenylselenation of Phenols: Scope and Applications
Xiong, Xiaodong,Yeung, Ying-Yeung
, p. 4033 - 4043 (2018/05/22)
An ortho-selective ammonium chloride salt-catalyzed direct C-H monohalogenation of phenols and 1,1′-bi-2-naphthol (BINOL) with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) as the chlorinating agent has been developed. The catalyst loading was low (down to 0.01 mol %) and the reaction conditions were very mild. A wide range of substrates including BINOLs were compatible with this catalytic protocol. Chlorinated BINOLs are useful synthons for the synthesis of a wide range of unsymmetrical 3-aryl BINOLs that are not easily accessible. In addition, the same catalytic system can facilitate the ortho-selective selenylation of phenols.
Regioselective Halogenation of Arenes and Heterocycles in Hexafluoroisopropanol
Tang, Ren-Jin,Milcent, Thierry,Crousse, Benoit
, p. 930 - 938 (2018/01/28)
Regioselective halogenation of arenes and heterocycles with N-halosuccinimides in fluorinated alcohols is disclosed. Under mild condition reactions, a wide diversity of halogenated arenes are obtained in good yields with high regioselectivity. Additionally, the versatility of the method is demonstrated by the development of one-pot sequential halogenation and halogenation-Suzuki cross-coupling reactions.
In Situ Formed IIII-Based Reagent for the Electrophilic ortho-Chlorination of Phenols and Phenol Ethers: The Use of PIFA-AlCl3 System
Nahide, Pradip D.,Ramadoss, Velayudham,Juárez-Ornelas, Kevin A.,Satkar, Yuvraj,Ortiz-Alvarado, Rafel,Cervera-Villanueva, Juan M. J.,Alonso-Castro, ángel J.,Zapata-Morales, Juan R.,Ramírez-Morales, Marco A.,Ruiz-Padilla, Alan J.,Deveze-álvarez, Martha A.,Solorio-Alvarado, César R.
, p. 485 - 493 (2018/02/09)
A new and in situ formed reagent generated by mixing PIFA {bis[(trifluoroacetoxy)iodobenzene]} and AlCl3 was introduced in the organic synthesis for the direct and highly regioselective ortho-chlorination of phenols and phenol ethers. An efficient electrophilic chlorination for these electron-rich arenes as well as the scope of the reaction are described herein. An easy, practical, and open-flask reaction allowed us to introduce a chlorine atom, which is a highly important functional group in organic synthesis. The reproducibility of our method has been demonstrated on gram-scale by carrying out the reaction in 6-bromo-2-naphthol. This halogenation reaction also proceeds in excellent conditions by first preparing the iodine(III)-based chlorinating reagent. Our new chlorinating reagent can be stored at least for two weeks at 4 °C without losing its reactivity.
Iron(III)-Catalyzed Chlorination of Activated Arenes
Mostafa, Mohamed A. B.,Bowley, Rosalind M.,Racys, Daugirdas T.,Henry, Martyn C.,Sutherland, Andrew
, p. 7529 - 7537 (2017/07/26)
A general and regioselective method for the chlorination of activated arenes has been developed. The transformation uses iron(III) triflimide as a powerful Lewis acid for the activation of N-chlorosuccinimide and the subsequent chlorination of a wide range of anisole, aniline, acetanilide, and phenol derivatives. The reaction was utilized for the late-stage mono- and dichlorination of a range of target compounds such as the natural product nitrofungin, the antibacterial agent chloroxylenol, and the herbicide chloroxynil. The facile nature of this transformation was demonstrated with the development of one-pot, tandem, iron-catalyzed dihalogenation processes allowing highly regioselective formation of different carbon-halogen bonds. The synthetic utility of the resulting dihalogenated aryl compounds as building blocks was established with the synthesis of natural products and pharmaceutically relevant targets.
Aromatic Monochlorination Photosensitized by DDQ with Hydrogen Chloride under Visible-Light Irradiation
Ohkubo, Kei,Fujimoto, Atsushi,Fukuzumi, Shunichi
, p. 996 - 999 (2016/04/20)
Photochlorination of aromatic substrates by hydrogen chloride with 2,3-dichloro-5,6-cyano-p-benzoquinone (DDQ) occurs efficiently to produce the corresponding monochlorinated products selectively under visible-light irradiation. The yields for the chlorination of phenol were 70 % and 18 % for p- and o-chlorophenol, respectively, without formation of further chlorinated products. The photoinduced chlorination is initiated by electron transfer from Cl- to the triplet excited state of DDQ. The radical intermediates involved in the photochemical reaction have been detected by time-resolved transient absorption measurements.
