6735-55-3Relevant academic research and scientific papers
Raman spectroscopic investigation of tetraethylammonium polybromides
Chen, Xiaoyun,Rickard, Mark A.,Hull, John W.,Zheng, Chao,Leugers, Anne,Simoncic, Petra
, p. 8684 - 8689 (2010)
A large number of polyhalides, especially polyiodides, have been discovered and studied, but definitive studies on polybromides remain scarce. Br 3- is the only monovalent polybromide with a known structure. Higher-order monovalent polybromide anions have been proposed but not structurally confirmed as discrete species. In this study tetraalkylammonium polybromides with molecular formulas R4NBr2x+1 (R = ethyl; x = 1-4) were prepared by reacting tetraalkylammonium monobromide or tribromide salts with gas-phase bromine. Distinct and characteristic Raman spectra were obtained from the solid polybromides in the spectral range between 100 and 400 cm-1. Experimental Raman spectra were compared to ab initio calculations to propose the structure of these polybromide anions. A general agreement between the experimental and theoretical results was observed. This study demonstrates that Raman spectroscopy is a sensitive technique for probing the structure of discrete monovalent polybromides.
Controlling Stereoselectivity in Tribromide Mediated Oxidative Dearomatisations – Synthesis of Selective Spirofurano-naphthalones
Sarkar, Debayan,Kuila, Puspendu,Sood, Devashish
, p. 5894 - 5904 (2019/08/26)
A series of ammonium tribromides were screened for exploring the role of ammonium counterpart attached to tribromides on generation of stereoselective spiro-furans via oxidative dearomatisation of naphthols. The proposition enlightens a suitable combination of the ammonium tribromide and solvent employed, deliver the best achieved diastereoselectivities. This in turn, has also envisioned the mechanistic aspects related to this category of reactions. The mentioned dearomative spiro-furano naphthalones has also been successfully achieved on a large-scale.
Novel Metal- and Mineral-Acid-Free Synthesis of Organic Ammonium Tribromides and Application of Ethylenephenanthrolium Bistribromide for Bromination of Active Methylene Group of 1,3-Diketones and β-Ketoesters
Dey, Rupa Rani,Paul, Bappi,Dhar, Siddhartha Sankar
supporting information, p. 724 - 736 (2015/10/29)
A novel procedure for the preparation of organic ammonium tribromides (OATBs) is described from their corresponding bromides. Quaternary ammonium bromides (QABs) and a N,N′-heterocyclic dibromide are efficiently oxidized to their corresponding monotribromides and bistribromide by m-chloroperbenzoic acid (MCPBA) in the presence of 2 and 4 equiv of KBr, respectively. The reactions are carried out in an aqueous medium without the use of any mineral acid or metal catalyst/promoters. A variety of tribromides are synthesized in very good yields including a hitherto unknown reagent, 1,10-(ethane-1, 2-diyl)phenanthrolinediium bistribromide (EPDBT). EPDBT is investigated as brominating agent and found to be highly effective for selective bromination of active methylene groups of a variety of 1,3-diketones and β-ketoesters. GRAPHICAL ABSTRACT.
Sodium hypochlorite-promoted novel synthesis of organic ammonium tribromides and application of phenanthroline hydrotribromide in chemoselective oxidation of organic sulfides by hydrogen peroxide
Dey, Madhudeepa,Dey, Rupa R.,Dhar, Siddhartha S.
supporting information, p. 631 - 633 (2014/05/20)
A novel method of synthesis of organic ammonium tribromides (OATBs) is developed by using an inexpensive and eco-friendly sodium hypochlorite as oxidant for conversion of Br to Br3 . The OATBs thus prepared include both quaternary ammonium tribromides and N-heterocyclic tribromides. A new addition to the family of OATBs is made in the form of phenanthroline hydrotribromide. The efficacy of this new tribromide as catalyst is ascertained in the oxidative transformation of organic sulfides to their corresponding sulfoxides and sulfones by hydrogen peroxide.
Novel method of synthesis of quaternary ammonium tribromides and investigation of catalytic role of benzyltrimethylammonium tribromide in oxidation of alcohols to carbonyl compounds
Dey, Madhudeepa,Dhar, Siddhartha Sankar,Kalita, Mukul
, p. 1734 - 1742 (2013/05/22)
Stable crystalline organic quaternary ammonium tribromides (QATBs) have been easily synthesized by the oxidation of the corresponding organic ammonium bromides (QABs) with ammonium persulfate. The reactions have been performed under solvent-free conditions in the presence of sulfuric acid and silica as supporting agent. Two equivalents of potassium bromide have been used as the source of additional bromides for quantitative conversion of QABs to QATBs.Ammonium persulfate, a cheap and readily available oxidant, carries out the bromide oxidation to tribromide very effectively under solvent-free conditions. The synthesized QATBs have been shown to catalyze the oxidation of alcohols to carbonyl compounds with hydrogen peroxide as oxidant in good yields under mild reaction conditions. Copyright Taylor & Francis Group, LLC.
PROCESS FOR PREPARING QUATERNARY AMMONIUM TRIBROMIDES
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Page 11, (2010/02/07)
The present invention relates to an economical and environmentally clean process for the preparation of high quality quaternary ammonium tribromides by oxidation of bromide (Br-) in an acidic medium by a biomimetic process involving transition metal ion mediated activation of hydrogen peroxide.
