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Iranian dolomite (CaMg(CO3)2) which consists of double-layered carbonates with Ca2+ and Mg2+ ions was utilized as a heterogeneous base catalyst in the CC, CN, and CS bond forming reactions via the Henry, Knoevenagel, aza-Michael, and thia-Michael transformations under mild conditions in water. Iranian dolomite has been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer Emmett Teller (BET) and XRF chemical analysis, while its basic strength was evaluated by following the Hammett indicators procedure. This water-insoluble natural catalyst demonstrated high activity and was reusable.

A methodology has been developed for an efficient and selective lipase-catalyzed aza-Michael reaction of various amines (primary and secondary) with a series of acrylates and alkylacrylates. Reaction parameters were tuned, and under the optimal conditions it was found that Pseudomonas stutzeri lipase and Chromobacterium viscosum lipase showed the highest selectivity for the aza-Michael addition to substituted alkyl acrylates. For the first time also, some CLEAs were examined that showed a comparable or higher selectivity and yield than the free enzymes and other formulations.

Aza-Michael adducts are obtained in very good yields by the conjugate addition of aliphatic amines to α,β-unsaturated compounds using molecular iodine as catalyst in dichloromethane at room temperature. Aromatic amines were found to be reactive under reflux in toluene.

The efficient and very simple conjugate addition of aromatic and aliphatic amines to α,β-unsaturated carbonyl compounds under solvent-free conditions in the presence of catalytic amount of silicon tetrachloride is reported. The reaction of aryl and alkyl amines with different Michael acceptors gave the corresponding Michael adducts with simple catalyst and good to excellent yields. Georg Thieme Verlag Stuttgart New York.

Highly efficient solvent-free aza-Michael additions of a variety of amines to,-unsaturated carbonyl compounds under microwave-irradiation conditions catalyzed by perchloric acid impregnated on silica gel (HClO4/SiO2) is reported. The reactions are completed within 2-7min in a microwave oven to produce the corresponding adducts in excellent yields, and the catalyst can be recovered and reused.

A fast, mild, and quantitative procedure for Michael addition reactions between various amines and α,β-unsaturated carbonyl compounds and nitriles in the presence of an easily accessible basic ionic liquid - 3-butyl-1-methylimidazolium hydroxide, [bmIm]OH - as both catalyst and reaction medium has been developed. For large-scale reactions the products could be directly distilled from the ionic liquid, allowing the use of organic solvents to be avoided totally. The ionic liquid could be reused at least eight times with consistent activity and was stable during the reaction process. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.

A convenient and versatile method was developed for aza-Michael addition using a substoichiometric amount of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Various nitrogen nucleophiles were efficiently introduced to α,β-unsaturated carbonyl compounds employing 0.5 equiv of DBU. Furthermore, other heteroatomic nucleophiles could also be introduced successfully under the same reaction conditions.

Cellulose-supported copper(0) efficiently catalyzes the aza-Michael reaction of N-nucleophiles, such as amines and imidazoles with α,β-unsaturated compounds to produce the corresponding β-amino compounds and N-substituted imidazoles in excellent yields. The reactions are facile and the recovered catalyst is used for several cycles with consistent activity. Georg Thieme Verlag Stuttgart.

At room temperature, ZrOCl2·8H2O on montmorillonite K10 efficiently catalyzes conjugate addition of amines to a variety of conjugated alkenes such as α,β-unsaturated carbonyl compounds, carboxylic esters, nitriles and amides under solvent-free conditions. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency.

Boric acid efficiently catalyzes the conjugate addition of aliphatic amines to α,β-unsaturated compounds to produce β-amino compounds, with great alacrity and excellent yields, in water under mild conditions. Aromatic amines do not participate effectively in the reaction.

The 1,4-conjugate addition of primary, secondary and aromatic amines, thiols, and carbamate to α,β-unsaturated compounds mediated by a catalytic amount (0.5 mol%) of RuCl3 in poly(ethylene glycol) (PEG) provides the desired β-substituted carbonyls in high yields. In particular, we found that primary aliphatic and aromatic amines produced the single adducts as the sole products in very high yields with RuCl3-PEG. RuCl 3-PEG was readily recycled via solvent precipitation with efficient recyclability as evidenced by high yields. Its properties of low sensitivity toward moisture and oxygen, high tolerance of different functional groups, and efficient recyclability make RuCl3-PEG suitable for both laboratory and industrial scale synthesis of β-substituted carbonyls. Georg Thieme Verlag Stuttgart.

Copper(II) acetylacetonate immobilized in ionic liquids efficiently catalyzes the aza-Michael reaction of amines with α,β-unsaturated carbonyl compounds to produce the corresponding β-amino carbonyl compounds with great alacrity in excellent yields. The reactions are far more facile than those reported earlier. The recovered ionic liquid phase containing the copper catalyst can be reused for several cycles with consistent activity.

Several primary and secondary amines were added to α,β- unsaturated esters, nitriles, amides, and ketones to give the corresponding saturated amines mediated by solid lithium perchlorate under solvent-free and environmentally friendly conditions at room temperature.

A series of cationic (diphosphine)palladium(II) complexes have been prepared and fully characterized, including two crystal structures. These complexes were evaluated as catalysts for the hydroamination of acyclic alkenes. The reactivity of the catalysts is dependent on the nature of the diphosphine ligand and the substituents on the amine and alkene substrates.

Tripod ligands RC(CH2X)(CH2Y)(CH2Z) (X, Y, Z = NR2, PR2) are accessible from α,β-unsaturated esters R(=CH2)COOR′. The key steps in this synthetic approach are Michael additions of amines and phosphanes to produce RCH(COOR′)(CH2X) (X = NR2, PR2) (2 and 3), followed by hydroxymethylation with paraformaldehyde to result in RC(COOR′)(CH2OH)(CH2X) (X = NR2) (4). Standard transformations of this C1-symmetric precursor allow for the synthesis of tripod ligands such as PhC(CH2pz)(CH2PPh2)(CH2PMes) (11). Coordination of these ligands with d8-metal ions [nickel(II), palladium(II), rhodium(I)] results in square-planar complexes with the chelate cycles in half-chair, twist-boat or boat conformations, depending on the specific substitution pattern. Coordination through two phosphane donors with the nitrogen donor acting as a dangling arm is generally preferred throughout. Detail preparative procedures and complete characterisation by analytical methods, including X-ray analysis of the coordination compounds, are given. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.

Simple, heterogeneous base catalysts based on supported phenolates can be easily prepared and are very active and selective in the Michael reaction.