Novel transformations with borontrifluoride etherate/iodide ion : facile conversion of 2-ketooxiranes and 2-bromo-2-enones to the α,β-unsaturated carbonyl compounds
Halogenation of Carbonyl Compounds by an Ionic Liquid, [AcMIm]X, and Ceric Ammonium Nitrate (CAN)
作者:Brindaban C. Ranu、Laksmikanta Adak、Subhash Banerjee
DOI:10.1071/ch07061
日期:——
An ionic liquid, acetylmethylimidazolium halide ([AcMIm]X), in combination with ceric ammoniumnitrate promotes halogenations of a wide variety of ketones and 1,3-keto esters at the α-position. The ionic liquid acts here as reagent as well as reaction medium, and thus the reaction does not require any organic solvent or conventional halogenating agent. The reaction is completely arrested when the radical
离子液体乙酰甲基咪唑鎓卤化物 ([AcMIm]X) 与硝酸铈铵结合可促进多种酮和 1,3-酮酯在 α 位的卤化。离子液体在此既充当试剂又充当反应介质,因此该反应不需要任何有机溶剂或常规卤化剂。当使用自由基猝灭剂 TEMPO 时,反应完全停止。还提出了一种似是而非的激进机制。
Oxidation of α,β-enones and alkenes with oxone and sodium halides: A convenient laboratory preparation of chlorine and bromine
作者:R.Karl Dieter、Lois E. Nice、Sadanandan E. Velu
DOI:10.1016/0040-4039(96)00295-x
日期:1996.4
Mixtures of oxone and sodium chloride or sodium bromide afford solutions of chlorine or bromine, respectively. These solutions effectively add chlorine and bromine to α,β-enones and alkenes. The method affords improved yields of 3-alkyl-2-halo-2-cycloalkenones which are sometimes difficult to prepare.
Ionic Liquid as Reagent. A Green Procedure for the Regioselective Conversion of Epoxides to <i>V</i><i>icinal</i>-Halohydrins Using [AcMIm]X under Catalyst- and Solvent-Free Conditions
作者:Brindaban C. Ranu、Subhash Banerjee
DOI:10.1021/jo0500885
日期:2005.5.1
A variety of structurally diverse epoxides undergo facile cleavages by ionic liquid, [AcMIm]X without any catalyst and solvent to produce the corresponding vicinal halohydrins in high yields. The cleavages are considerably fast and highly regioselective.
Baker, Journal of the Chemical Society, 1926, p. 667