507-19-7Relevant articles and documents
1H NMR spectroscopic study of the tert-butyl chloride - Aluminum bromide cationic initiating system
Murachev,Byrikhin,Nesmelov,Ezhova,Orlinkov
, p. 2149 - 2154 (1998)
The interaction of tert-butyl chloride with aluminum bromide in methylene dibromide at -30 °C leads to the formation of two types of adducts, which give signals with δ 2.4 and 3.2 in the 1H NMR spectra in addition to that of free alkyl halide. These signals are attributed to a polarized complex (PC) and ion pair (IP), respectively. An excess of AlBr3 shifts the equilibria toward IP. The latter contains more AlBr3 than the polarized complex. Based on the spectral data, we calculated the limiting values of some equilibrium constants. The ability of AlBr3 to solvate counterions is consistent with the results of isobutylene polymerization under the action of the initiating Bu1Cl-AlBr3 system at different ratios of the starting concentrations [AlBr3]0/[Bu1Cl]0. An increase in this ratio results in both the acceleration of polymerization and an increase in the relative role of chain transfer reactions.
A Convenient Method for the Preparation of Highly Pure t-Alkyl Bromides and Iodides
Masada, Hiromitsu,Murotani, Yoshiharu
, p. 1181 - 1182 (1980)
Highly pure (99-100 percent) t-butyl and t-pentyl bromides and iodides, and 3-bromo-3-ethylpentane were readily prepared in 83-95 percent yields by the reactions of the corresponding alcohols with hydrobromic or hydroiodic acid, using lithium or calcium halide.The metal halides remarkably increased the yield and the purity of the products.
Thiourea-Mediated Halogenation of Alcohols
Mohite, Amar R.,Phatake, Ravindra S.,Dubey, Pooja,Agbaria, Mohamed,Shames, Alexander I.,Lemcoff, N. Gabriel,Reany, Ofer
, p. 12901 - 12911 (2020/11/26)
The halogenation of alcohols under mild conditions expedited by the presence of substoichiometric amounts of thiourea additives is presented. The amount of thiourea added dictates the pathway of the reaction, which may diverge from the desired halogenation reaction toward oxidation of the alcohol, in the absence of thiourea, or toward starting material recovery when excess thiourea is used. Both bromination and chlorination were highly efficient for primary, secondary, tertiary, and benzyl alcohols and tolerate a broad range of functional groups. Detailed electron paramagnetic resonance (EPR) studies, isotopic labeling, and other control experiments suggest a radical-based mechanism. The fact that the reaction is carried out at ambient conditions, uses ubiquitous and inexpensive reagents, boasts a wide scope, and can be made highly atom economic, makes this new methodology a very appealing option for this archetypical organic reaction.
Metal- and base-free synthesis of aryl bromides from arylhydrazines
Phuc Tran, Dat,Nomoto, Akihiro,Mita, Soichiro,Dong, Chun-ping,Kodama, Shintaro,Mizuno, Takumi,Ogawa, Akiya
supporting information, (2020/05/08)
An efficient method was developed to synthesize brominated aromatic compounds from arylhydrazine hydrochlorides by using BBr3 in DMSO/CPME (cyclopentyl methyl ether) under air at 80 °C for 1 h without the use of bases or metal catalysts. In particular, this method could be carried out satisfactorily using electron-withdrawing groups to afford aryl bromides in a moderate to excellent yields.
Reliably Regioselective Dialkyl Ether Cleavage with Mixed Boron Trihalides
Atienza, Bren Jordan P.,Truong, Nam,Williams, Florence J.
supporting information, p. 6332 - 6335 (2018/10/09)
A protocol for the regioselective cleavage of unsymmetrical alkyl ethers to generate alkyl alcohol and alkyl bromide products is described. A mixture of trihaloboranes triggers this conversion and exhibits improved reactivity profiles (regioselectivity and yield) compared with BBr3 alone. Additionally, this procedure allows the efficient synthesis of (B-Cl) dialkyl boronate esters. There are limited methods to generate acyclic dialkoxyboryl chlorides, and these intermediates constitute important synthons in main-group chemistry.
A mild method for the replacement of a hydroxyl group by halogen. 1. Scope and chemoselectivity
Munyemana, Fran?ois,George, Isabelle,Devos, Alain,Colens, Alain,Badarau, Eduard,Frisque-Hesbain, Anne-Marie,Loudet, Aurore,Differding, Edmond,Damien, Jean-Marie,Rémion, Jeanine,Van Uytbergen, Jacqueline,Ghosez, Léon
, p. 420 - 430 (2015/12/31)
α-Chloro-, bromo- and iodoenamines, which are readily prepared from the corresponding isobutyramides have been found to be excellent reagents for the transformation of a wide variety of alcohols or carboxylic acids into the corresponding halides. Yields are high and conditions are very mild thus allowing for the presence of sensitive functional groups. The reagents can be easily tuned allowing therefore the selective monohalogenation of polyhydroxylated molecules. The scope and chemoselectivity of the reactions have been studied and reaction mechanisms have been proposed.
Catalytic phosphorus(V)-mediated nucleophilic substitution reactions: Development of a catalytic appel reaction
Denton, Ross M.,An, Jie,Adeniran, Beatrice,Blake, Alexander J.,Lewis, William,Poulton, Andrew M.
experimental part, p. 6749 - 6767 (2011/10/02)
Catalytic phosphorus(V)-mediated chlorination and bromination reactions of alcohols have been developed. The new reactions constitute a catalytic version of the classical Appel halogenation reaction. In these new reactions oxalyl chloride is used as a consumable stoichiometric reagent to generate the halophosphonium salts responsible for halogenation from catalytic phosphine oxides. Thus, phosphine oxides have been transformed from stoichiometric waste products into catalysts and a new concept for catalytic phosphorus-based activation and nucleophilic substitution of alcohols has been validated. The present study has focused on a full exploration of the scope and limitations of phosphine oxide catalyzed chlorination reactions as well as the development of the analogous bromination reactions. Further mechanistic studies, including density functional theory calculations on proposed intermediates of the catalytic cycle, are consistent with a catalytic cycle involving halo- and alkoxyphosphonium salts as intermediates.
Silver-catalyzed benzylation and allylation of tertiary alkyl bromides with organozinc reagents
Mitamura, Yukihiro,Asada, Yoshihiro,Murakami, Kei,Someya, Hidenori,Yorimitsu, Hideki,Oshima, Koichiro
experimental part, p. 1487 - 1493 (2011/07/07)
Silver salts catalyze the benzylation and allylation of tertiary alkyl bromides with organozinc reagents. The reactions create quaternary carbon centers efficiently. Treatment of gem-dibromoalkanes with benzylic or allylic zinc reagents under silver catalysis leads to dibenzylation or diallylation. The functional-group compatibility of the present reactions is wider than that of the previous reactions with Grignard reagents.
Silicaphosphine (Silphos): A filterable reagent for the conversion of alcohols and thiols to alkyl bromides and iodides
Iranpoor, Nasser,Firouzabadi, Habib,Jamalian, Arezu,Kazemi, Foad
, p. 5699 - 5704 (2007/10/03)
Silicaphosphine (Silphos), [P(Cl)3-n(SiO2) n], as a new heterogeneous reagent is introduced. This reagent converts alcohols and thiols to their corresponding bromides and iodides in the presence of X2 (X=Br, I) in refluxing CH3CN in high to quantitative yields. Use of Silphos provides a highly practical method for the easy separation of the Silphos oxide byproduct by a simple filtration.
INTEGRATED PROCESS FOR SYNTHESIZING ALCOHOLS, ETHERS, AND OLEFINS FROM ALKANES
-
, (2008/06/13)
Alcohols, ethers, and olefins are manufactured from alkanes by mixing an alkane and bromine in a reactor to form alkyl bromide and hydrogen bromide. The alkyl bromide only or the alkyl bromide and the hydrogen bromide are directed into contact with metal oxide to form an alcohol and/or an ether, or an olefin and metal bromide. The metal bromide is oxidized to form original metal oxide and bromine, both of which are recycled.
