Layered Double Hydroxides-Supported Diisopropylamide: Synthesis, Characterization and Application in Organic Reactions
作者:M. Lakshmi Kantam、A. Ravindra、Ch. Venkat Reddy、B. Sreedhar、B. M. Choudary
DOI:10.1002/adsc.200505266
日期:2006.3
The layereddoublehydroxides-supporteddiisopropylamide (LDH-DA) catalyst is found to be an efficient and selective solid base for aldol, Knoevenagel, Henry, Michael, transesterification and epoxidation reactions under liquid phase conditions. LDH-DA is synthesized by the interaction of lithium diisopropylamide with LDH-NO3 (as-synthesized) and calcined LDH-NO3. The LDH-DA (Mg/Al, 3/1) and their precursors
发现层状双氢氧化物负载的二异丙基酰胺(LDH-DA)催化剂是在液相条件下用于醇醛,Knoevenagel,Henry,Michael,酯交换和环氧化反应的有效且选择性的固体碱。LDH-DA是通过二异丙基氨基锂与LDH-NO 3(合成后)和煅烧的LDH-NO 3相互作用而合成的。通过使用各种仪器技术,如FT-IR,TGA和DTA,粉末XRD,固态27 Al MAS NMR光谱,SEM和XPS(ESCA ),可以很好地表征LDH-DA(Mg / Al,3/1)及其前体)。
The Michael reaction, with conjugate bases of β-diketones as donors and with α,β-unsaturatedketones as acceptors, is efficiently catalyzed by a combination of clay-supported nickel bromide (heterogeneous) and ferric chloride (homogeneous).
The LBAs (Lewis acid-assisted Brønsted acidcatalysis) is proposed as possible mechanistic process in the simple FeCl3-catalyzed Michael reactions of chalcones with active methylene compounds in organic solvents. And iron salts were found to be effective promoters in the asymmetricMichaeladdition of 4-hydroxycoumarin to α,β-unsaturated ketone, which resulted in excellent yield and high level of enantioselectivity
New Application of 1,4-Dihydropyridine System: Michael Reactions Mediated by 1,4-Dihydropyridine–Enolate Adduct in Micellar Medium
作者:Sabir H. Mashraqui、Madhavi A. Karnik
DOI:10.1246/cl.2003.1064
日期:2003.11
1,4-dihydropyridine-acetophenone enolate adduct, in catalytic amount effects Michael reactions in aqueous cationic micelles of cetyltrimethylammonium bromide. The enolate, generated by dissociation of the adduct abstracts a proton from readily enolizable substrates to bring about the Michael reaction under mild conditions in fair to good yields without side products.
Polyaniline-Anchored Metal Salts for Michael Reaction of <font>α</font>,<font>β</font>-Unsaturated Ketones
作者:Arun L. Patel、Harish R. Talele、H. S. Rama、Ashutosh V. Bedekar
DOI:10.1080/00397910802664277
日期:2009.7.29
Abstract A catalyst consisting of polyaniline-anchored metal salts is used as a Lewis acid to promote the Michaelreaction of α,β-unsaturated ketones. The reaction is performed efficiently with imidazole, acetyl acetone, and ethyl acetate as Michel donors and chalcones as the acceptors under ultrasound irradiation.