当在丙酮中用卤化锂在回流下处理时,被修饰为对甲苯磺酸盐,PEG-磺酸盐或对甲苯磺酸盐的仲醇在反应中心发生构型转化,其中PEG-磺酸盐和对甲苯磺酸盐的反应性更高。在空间受限的情况下,淘汰是一个相互竞争的过程。相反,当用TiCl 4处理时,简单的仲磺酸盐使氯化物产物的构型部分反转。在这些条件下,在给定的烷基磺酸盐底物中观察到的任何构型保留都可能是由于相邻基团的参与或对碳正离子(或离子对)的非对映选择性攻击,而不是S N i机理。
Reactivity of bismuth(III) halides towards alcohols. A tentative to mechanistic investigation
作者:El Mehdi Keramane、Bernard Boyer、Jean-Pierre Roque
DOI:10.1016/s0040-4020(01)00013-8
日期:2001.3
bismuth(III) halides (BiX3; X=Cl, Br and I) towards a series of alcohols has been investigated. Three different reactions have been studied, namely: halogenation, dehydration and etherification. The behaviour of these bismuth derivatives was found to depend on the nature of the halide bonded to the bismuth atom. Their reactivities can be interpreted on the basis of the Hard and Soft Acids and Bases
研究了卤化铋(III)(BiX 3; X = Cl,Br和I)对一系列醇的反应性。已经研究了三种不同的反应,即:卤化,脱水和醚化。发现这些铋衍生物的行为取决于结合到铋原子上的卤化物的性质。它们的反应性可以根据硬酸和软酸和碱(HSAB)原理进行解释。提出了一种机制,该机制涉及形成醇与Bi(III)的复合物。
Stereoretentive Chlorination of Cyclic Alcohols Catalyzed by Titanium(IV) Tetrachloride: Evidence for a Front Side Attack Mechanism
作者:Deboprosad Mondal、Song Ye Li、Luca Bellucci、Teodoro Laino、Andrea Tafi、Salvatore Guccione、Salvatore D. Lepore
DOI:10.1021/jo3023439
日期:2013.3.1
A mild chlorination reaction of alcohols was developed using the classical thionyl chloride reagent but with added catalytic titanium(IV) chloride. These reactions proceeded rapidly to afford chlorination products in excellent yields and with preference for retention of configuration. Stereoselectivities were high for a variety of chiral cyclic secondary substrates including sterically hindered systems
Metal-free regioselective hydrochlorination of unactivated alkenes<i>via</i>a combined acid catalytic system
作者:Shengzong Liang、Gerald B. Hammond、Bo Xu
DOI:10.1039/c7gc03665e
日期:——
A combined acid HCl/DMPU-acetic acid catalytic system was used in the hydrochlorination of a wide range of unactivated alkenes.
一个结合了盐酸/HCl、DMPU和乙酸的催化体系被用于对一系列未活化的烯烃进行氯化反应。
Iron(III)-Catalyzed Halogenations by Substitution of Sulfonate Esters
作者:Nuria Ortega、Andrés Feher-Voelger、Margarita Brovetto、Juan I. Padrón、Victor S. Martín、Tomás Martín
DOI:10.1002/adsc.201000740
日期:2011.4.18
A novel halogenation reaction from sulfonates catalyzed by iron(III) is described. The reaction can be performed as a stoichiometric or a catalytic version. This reaction provides a convenient strategy for the efficient access to structurally diverse secondary chlorides, bromides and iodides. The stereochemical course of the reaction is governed by the substrate and the experimental conditions. Secondary
Method for producing organic compounds by substituting halogen atoms
申请人:MITSUI CHEMICALS, INC.
公开号:EP1486479A1
公开(公告)日:2004-12-15
The invention pertains to a method in which a halogen atom of an organic compound is replaced with a group derived from a nucleophilic agent, at high yield and high efficiency, by the following method which includes a step of reacting the nucleophilic agent with an organic material having a halogen atom bonded to a carbon atom having four σ bonds, more specifically: a method for producing an organic compound having Q, the method including a step of reacting a compound represented by general formula (2) with an organic starting material having at least one halogen atom bonded to a carbon atom having four σ bonds so as to replace the halogen atom in the organic starting material with Q:
MQa (2)
(wherein M represents an alkali metal atom, an alkali earth metal atom, or a rare earth metal atom; Q represents a moiety of an inorganic acid or an active hydrogen compound derived by eliminating a proton, wherein Q is a halogen atom different from the halogen atom in the organic starting material having the halogen atom bonded to the carbon atom having the four σ bonds; and a represents an integer of 1 to 3) in the presence of a compound represented by general formula (1)
(wherein Z- represents an anion derived by eliminating a proton from an inorganic acid or an active hydrogen compound; R2 is the same or different; R2 each independently represent a C1-C10 hydrocarbon group or two R2 on the same nitrogen atom may be bonded with each other to form a ring with the nitrogen atom).