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。
Ferric(III) Chloride Catalyzed Halogenation Reaction of Alcohols and Carboxylic Acids Using α,α-Dichlorodiphenylmethane
作者:Chang-Hee Lee、Soo-Min Lee、Byul-Hana Min、Dong-Su Kim、Chul-Ho Jun
DOI:10.1021/acs.orglett.8b00831
日期:2018.4.20
conversions of various alcohols and carboxylic acids to their corresponding alkyl and acyl chlorides in high yields under mild conditions. Particulary interesting is the observation that the respective alkyl bromides and iodides can be generated from alcohols when either LiBr or LiI are present in the reaction mixtures.
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
Catalytic decomposition of alkyl chloroformates by hexabutylguanidinium chloride
作者:Frédérique Foulon、Bernard Fixari、Dominique Picq、Pierre Le Perchec
DOI:10.1016/s0040-4039(97)00626-6
日期:1997.5
Hexabutylguanidinium chloride (0.5 molar %) efficiently decomposes alkylchloroformates into chlorides, with low alkenes formation, via a SN2 mechanism as demonstrated from substituents effects and asymmetric chloridesynthesis.
六丁基胍氯化物(0.5摩尔%)可以通过取代基效应和不对称氯化物合成证明的S N 2机理,将烷基氯甲酸酯有效地分解为氯化物,且烯烃形成率低。
Synthesis of alkyl halides under neutral conditions
Abstract Secondary alkyl chlorides have been efficiently prepared from secondary alkyl sulfonates under mild and user-friendly conditions. The exchange reaction was generally performed by using benzyltributylammonium chloride in acetone (reflux, 30 min). Yields are excellent from functionalized, base-sensitive and hindered secondary alkyl sulfonates. Secondary alkyl chlorides have been efficiently