Crown Ether Complex Cation Ionic Liquids: Preparation and Applications in Organic Reactions
作者:Yingying Song、Huanwang Jing、Bo Li、Dongsheng Bai
DOI:10.1002/chem.201100112
日期:2011.7.25
cation ionicliquids (CECILs) were designed, synthesised and characterised by NMR spectroscopy, HRMS, thermogravimetric differential thermal analysis (TG‐DTA) and elemental analysis. Their applications in various organic reactions were investigated: [15‐C‐5Na][OH], [15‐C‐5Na][OAc], [18‐C‐6K][OH] and [18‐C‐6K][OAc] (15‐C‐5=[15]crown‐5; 18‐C‐6=[18]crown‐6) efficiently catalysed the Michael addition of alkenes
predominantly catalyze Michael addition reactions. Inorganic and organic base‐catalyzed Michael addition reactions have been reported. However, known base‐catalyzedreactions suffer from the requirement of solvents, additives, high pressure and also side‐reactions. Herein, we demonstrate a mild and environmentally friendly strategy of readily available KOtBu‐catalyzed Michael addition reactions. This simple
Catalysis by an ionic liquid: efficient conjugate addition of thiols to electron deficient alkenes catalyzed by molten tetrabutylammonium bromide under solvent-free conditions
作者:Brindaban C Ranu、Suvendu S Dey、Alakananda Hajra
DOI:10.1016/s0040-4020(03)00289-8
日期:2003.3
An inexpensive and readily available ionic liquid, tetrabutylammonium bromide in the molten state, efficiently catalyzes the conjugateaddition of thiols to α,β-unsaturated nitriles, carboxylic ester, ketones and aldehydes as well as nitro olefins.
Abstract Potassium fluoride supported on aluminaefficientlycatalyzes Michael addition of aromatic and aliphatic thiols to a variety of conjugated alkenes such as α,β‐unsaturated carbonyl compounds, carboxylic esters, amides, nitriles and chalcones. The Michael adducts are produced in good to excellent yields and relatively in short times. The catalyst can be recycled for subsequent reactions without
Abstract A facile two-step synthesis of methylketones from alkyl nitriles via the Blaise conversion of nitriles into β-keto esters and acid-mediated hydrolysis followed by decarboxylation of the resulting β-keto esters is described.